ICT Applications (BIT2103)
1. Course Outline ... 2
2. CHAPTER 1: Origin and development of computers ... 4
2.1. Definitions of key terminologies ... 4
2.2. Characteristics of Computers ... 6
3.1. History of Computers ... 7
6.1. Levels of management: ... 12
7. CHAPTER 2: COMPUTER HARDWARE ... 13
7.1. Definition ... 13
7.2. Input Devices ... 14
7.3. Processor Unit ... 14
7.3.1. RISC Vs CISC processors ... 14
7.5. Output devices ... 15
7.6. Storage Devices ... 16
7.7. Networking equipment ... 16
7.8. Types of Computers ... 16
8. CHAPTER 3: COMPUTER SOFTWARE ... 17
8.1. Types of software ... 17
8.2. System Software ... 17
8.3. Firmware... 17
8.4. Operating systems ... 17
8.5. Utility programs ... 18
8.6. Application software ... 18
8.7. Application Packages Used to Support End-User Computing ... 19
9. CHAPTER 4: CONTROLLING INFORMATION SYSTEMS ... 19
10.1. Threats to data ... 19
10.2. Administrative controls versus system controls ... 19
10.3. Physical versus logical controls ... 20
11.1. Examples of Data Security Controls ... 20
32. CHAPTER 5: Ms Word ... 22
32.1. Introduction to Ms Word ... 22
33. CHAPTER 6: Ms Excel ... 22
1. Course Outline
KyUC/F/AA/02 SCHOOL OF BUSINESS
COURSE OUTLINE
HBC 2106: FOUNDATION OF COMPUTER SYSTEMS DEPARTMENT ________COMMERCE_________________
PROGRAMME: __BACHELOR OF COMMERCE_ YEAR: ____1____
SEMESTER: __1_
UNIT CODE: ______HBC 2106_______ UNIT TITLE: FOUNDATION OF COMPUTER SYSTEMS
LECTURE HOURS: _________45_______________ PRE-REQUISITES:
______NONE__________
LECTURER: _________________GEOFFREY GITAU__________________________________
LECTURER CONTACTS: EMAIL: [email protected]____ TEL: __0721319897___
1.0.COURSE PURPOSE
________________________________________________________________________________
____________ The Course provides a fundamental understanding of computer fundamentals and computer
Applications with the course focus on the Microsoft Office Applications (Microsoft Word, Microsoft Excel and Microsoft PowerPoint). _________
2.0.LEARNING OUTCOMES
Students shall be able apply basic concepts in Computer Hardware, Software, Operating Systems, Telecommunications, as well as the usage of the Internet in various business areas.
COURSE OUTLINE
Week Topic Sub-topic Remarks
1 ICT concepts Definition of key terminologies: computer,
data, components of a computer system Class lecture 2 ICT concepts History of computers, computer generations Class lecture 3 ICT concepts Analogue versus digital computers, types of
computers, advantages and disadvantages of
Class lecture
computers. Data representation in a
computer: Bits, bytes, word, ASCI, EBCDIC, Computer architecture (RISC and CISC) 4 ICT concepts Computer hardware: Input devices, the
processor, output devices, storage devices and data communication systems
Class lecture
5 CAT 1 CAT1 Sit – in CAT
6 ICT concepts Data security controls: threats to data, administrative controls, system controls, physical controls and logical controls
Class lecture 7 ICT concepts Internet and email: definitions of key terms,
intranets and extranets, using email Lab exercise
8 Computer
applications
Ms Word: Ms Word desktop, creating a file, saving, spell checking, printing
Lab exercise
9 Computer
applications
Ms Word, create resume and mail merge Lab exercise 10 Computer
applications
Ms Excel: cell address, range, formula and
functions Lab exercise
11 Computer applications
Ms Excel: Creating invoices and receipts
Lab exercise
12 CAT 2 CAT 2: Lab practical Lab exam
13 Computer applications
Ms Power point: creating presentations Lab exercise
14 Revision Revision Tutorial exercises
3.0. TEACHING METHODOLOGY
Lecture, demonstration, lab exercises, individual and group assignments
4.0. INSTRUCTIONAL MATERIALS
_______Lecture handouts, computers, whiteboard, LCD projector__________
5.0. COURSE EVALUATION CAT 1 = _____10_________%
CAT 2 = _____10_________%
OTHER ASSESSMENTS= ____10_____%
Examination = _____70_______%
Total =100%
Pass mark: ______40__________%
6.0. COURSE TEXTBOOKS
Vermaat, M., E. (2013). Discovering Computers & Microsoft Office 2013: A Fundamental Combined Approach. Cengage Learning. Boston, M.A.
7.0.REFERENCE TEXTBOOKS
Shelly, G. B., Cashman, T. J., & Vermatt, M. E. (2006). Discovering computers 2006: A gateway to information, web enhanced complete. Boston: Thomson Course Technology.
8.0.COURSE JOURNALS
Fulantelli, G. and Allegra, M. (2003). Small company attitude towards ICT based solutions;
some key elements to improve it. Journal of Educational Technology and Society, 6(1): 45- 49.
REFERENCE JOURNALS
Chacko, G. & Harris, G. (2006). Information and Communication Technology and Small, Medium and Micro Enterprises in Asia-Pacific – size does not matter. Information Technology for Development, 12(2): 175-177.
2. CHAPTER 1: Origin and development of computers
2.1. Definitions of key terminologies Introduction:
This topic covers Introduction to the basics of IT/IS, distinguishing data from information, digital vs analog systems, computer storage (bits, bytes, word, kilobytes, gigabytes, etc.) , data representation (binary, octal, decimal and hex), data coding systems (ASCII and EBCDIC), advantages and disadvantages of computers, staff in an IT department
Definition of Computer
• A computer is a programmable machine. that accepts data input to process it by use of a specific set of instructions (a program) so as to provide output (information).
• Modern computers are electronic and digital in contrast to analog computers which would be electromechanical measuring devices. The actual physical components -- wires, transistors, and circuits -- is called hardware; the instructions and data are called software.
A computer could be special purpose or general-purpose. A special purpose computer means it is designed for specific use and cannot be reprogrammed to do any other job. For example electronic fuel pump, cash registers, ETR machine, etc. On the other hand general purpose computers will do any functions the user wants depending on the program loaded and hardware components connected.
Data versus Information
Data: Consists of facts, text, graphics and figure that have not been processed and inadequate for user’s application; e.g. Receipts of all goods purchased, unprocessed students marks, supplier orders awaiting processing, etc.
Information: A processed data that is sorted, useful and valuable for particular user, e.g. Sales reports, exam results, price list, etc.
Types of computers (according to processing capacity or size) Today’s computer systems fall into one of the following categories:
1. Supercomputers 2. Mainframe Computers
3. Minicomputers or Midrange Computers 4. Microcomputers, or personal computers Supercomputers:
• Most powerful computer made
• Physically they are the largest
• Process huge amounts of data
• Can house thousands of processors
• Relatively rare because of size and cost.
• Used by large corporations, universities and government agencies.
Mainframe Computers
• Used in large organizations like insurance companies, and banks where many people need frequent access to the same data, which is usually organized into one or more databases.
• Airlines, Government Agencies (Kenya National Bureau of Statistics, KRA, KPA, Metrological department, etc) track information about large populations, individual tax records, payroll, and more.
• Are being used more and more as specialized servers on the World Wide Web, enabling companies to offer secure transactions with customers over the Internet.
• Many enterprises are connecting personal computers and personal computer networks to their mainframe system. This allows access to the mainframe data and services and also enables them to take advantage of local storage and processing, as well as other features of the PC or network.
• Houses an enormous volume of data (literally billions of records)
• Mainframe can occupy entire rooms or even an entire floor of a high-rise building.
Special air conditioning systems are used to keep them cool and on raised floors to accommodate all the wiring needed to connect the system.
Minicomputers
• Abbreviated version of mainframe computers.
• The capabilities are somewhere between mainframes and PC.
• Minicomputers can handle much more input and output than personal computers can.
• Designed for a single user, most are designed to handle multiple terminals.
• Can be used as a server for PC’s Microcomputers, or Personal Computers
• The microcomputer is “the computer for the masses” and personal computing
• Microcomputers include the following types: Desktop models, including workstations, notebook computers (laptops), Network Computers (netbooks), Mini laptops and Handheld personal computers, PDAs
2.2. Characteristics of Computers
3. Characteristics of Computers
The characteristics of computers that have made them so powerful and universally useful are speed, accuracy, diligence, versatility and storage capacity.
Speed
Computers work at an incredible speed. The speed with which it performs is way beyond human capabilities. As a comparison, it can do in one minute what a human being would probably take a lifetime!
When we refer to the speed of computers, we now talk in terms of milliseconds (hundredth of a second), microseconds (millionth of a second), nanoseconds (billionth of a second), and even picoseconds (trillionth of a second). A powerful computer is capable of performing about 3-4 million simple instructions per second.
Accuracy
In addition to being fast, computers are also accurate. Errors that may occur can almost always be attributed to human error (inaccurate data, poorly designed system or faulty
instructions/programs written by the programmer) rather than technological weaknesses. In fact, a special term GIGO (Garbage In Garbage Out) has been coined to represent a scenario where faulty results are got due to inaccurate instructions or faulty data.
Diligence
Unlike human beings, computers are highly consistent. They do not suffer from human traits of boredom and tiredness resulting in lack of concentration. Computers, therefore, score high over human beings in performing voluminous and repetitive jobs.
Versatility
Computers are versatile machines and are capable of performing any task as long as it can be broken down into a series of logical steps. This means that their capability is, once again, limited only by human intelligence. As is evident, in today’s fast developing technology- world, it is almost inconceivable to find an area where computers are not being used. The presence of computers can be seen in every sphere – Railway/Air reservation, Banks, Hotels, Weather forecasting and many more.
Storage Capacity
Today’s computers can store volumes of data. Unlike human memory where unimportant information is relegated to the back of the mind and forgotten as time progresses, a piece of information once recorded (or stored) in the computer, can never be forgotten and can be retrieved almost instantaneously! Information can, therefore, be retained as long as desired (using secondary storage – a type of detachable memory).
3.1. History of Computers
The history of computers can be traced back to almost 2000 years ago, with the advent of abacus, a wooden rack holding two horizontal wires with beads strung on them. Numbers are represented using the position of beads on the rack. Fast and simple calculations can be carried out by appropriately placing the beads.
In 1620, an English mathematician by the name William Oughtred invented the slide rule – a calculating device based on the principle of logarithms. It consisted of two graduated scales devised in such a manner that suitable alignment of one scale against the other, made it possible to perform additions, compute products etc. just by inspection.
Blaise Pascal, a French mathematician, is usually credited for building the first digital computer in 1642. He invented the mechanical calculating machine. Numbers were entered in this machine by dialing a series of numbered wheels. Another series of toothed wheels transferred the movements to a dial, which showed the results.
In 1671, Gottfried von Leibnitz, a German mathematician, invented a calculating machine which was able to add and perform multiplications. He invented a special stepped gear mechanism for introducing the addend digits, which is still being used.
The prototypes made by Pascal and Leibnitz were not used in many places. It was only about a century later that Thomas of Colmar created the first successful mechanical calculator which could add, subtract, multiply, and divide. A lot of improved desktop calculators by various inventors followed, such that by 1890 a range of improvements like accumulation of partial results, storage of past results, and printing of results were not uncommon.
4. 1.3.1 The First Computer
Charles Babbage, a professor of mathematics at Cambridge University, England, realized that many long calculations usually consisted of a series of actions that were constantly repeated and hence could possibly be automated. By 1822, he designed an automatic calculating machine that he called the ‘Difference Engine’. It was intended to be steam powered and fully automatic (including printing of result tables), commanded by a fixed instruction program. In short, he developed a prototype of a computer which was 100 years ahead of time and is, therefore, considered as the father of modern day computers.
A step towards automated computing was the development of punched cards which were first successfully used by Herman Hollerith, who worked in the US Census Bureau in 1890. He along with James Powers developed devices that could read information that had been punched into cards, without any human help. This resulted in reduced reading errors, increased workflow and availability of unlimited memory (punched cards could be used as easily accessible memory of unlimited size).
These advantages were seen by various commercial companies and soon led to the development of improved punch-card using computers by companies like International Business Machines (IBM) and Remington.
5. 1.3.2 Some Well Known Early Computers
Mark I
After World War II there was a need felt for advanced calculations. By that time, many reliable mechanical desk calculators had been developed. Howard A. Aiken of Harvard University, while working on his doctorate in physics, in the year 1937, designed a machine that could automatically perform a sequence of arithmetic operations. He completed this in 1944 and named it Mark I. This machine performed a multiplication and division at an average of about four and eleven seconds respectively. The results were printed at a rate of one result per five seconds.
ENIAC
The World War II also produced a large need for computer capacity especially for the military. New weapons were made for which trajectory tables and other essential data were
needed. In 1942, Professors
John P. Eckert and John W. Mauchly at the Moore School of Engineering of the University of Pennsylvania, USA, decoded to build a high speed computer to do the job. This was called the Electronic Numeric Integrator and Calculator (ENIAC).
It used 18,000 vacuum tubes, about 1,800 square feet of floor space, and consumed about 180,000 watts of electrical power. It had punched cards I/O and its programs were wired on boards.
ENIAC is accepted as the first successful high-speed electronic digital computer and was used from 1946 to 1955.
EDVAC
Fascinated by the success of ENIAC, John Von Neumann, a mathematician, undertook an abstract study of computation in 1945. In this he aimed to show that a computer should be able to execute any kind of computation by means of a proper programmed control. His ideas, referred to as ‘stored program technique’, became essential for future generations of high- speed digital computers and were universally accepted. The basic idea behind the stored
program concept was that data as well as instructions can be stored in the computer’s memory to enable automatic flow of operations.
Between 1947 and 1950, the More School personnel and the Ballistics Research Laboratory of the US army built a computer named Electronic Discrete Variable Automatic Computer (EDVAC), which was based on Von Neumann’s concept of stored program.
UNIVAC
The Universal Automatic Computer (UNIVAC), developed in 1951, was the first digital computer to be produced and was installed in the Census Bureau.
The first-generation stored-program computers needed a lot of maintenance, reached 70% to 80% reliability of operations and were used for almost 10 years. EDVAC and UNIVAC fell into this group of computers and were the first commercially available computers.
6. 1.3.3 Computer Generations
‘Generation’ in computer terminology is a ‘step’ ahead in technology. As you go through the history of evolution of computers, you will find that the earliest computers were big in size, consumed a lot of power and heated up quickly, due to which it had to be shut down, frequently to be cooled. They were very expensive in terms of development and maintenance.
As technology improved, computers became compact, faster and more powerful. From a user’s perspective, they become user friendly and more affordable. This has largely contributed towards the popularity that computers have gained these days.
The term ‘generation’ was earlier used only to distinguish between varying hardware technologies but was later extended to include both hardware and software. A comparison of generations is made below.
First Generation Computers (1940 to 1956)
The first generation of computers was characterized by vacuum tubes in the circuitry and magnetic drums for memory.
These computers were enormous in size, used great deal of electricity and were expensive to operate. They also had limited storage capacity.
First generation computers relied on machine language (binary-coded program) to perform operations and could solve only one problem at a time. Punched cards and paper tapes were used to input data and instructions, and output was displayed on printouts.
Early computers like ENIAC, EDVAC and UNIVAC can all be classified as first generation computers.
Second Generation Computers (1956 to 1963)
In the early 1950s, the discoveries of Transistor and Magnetic core memory changed the image of computers – from unreliable to highly reliable machines with increased capability, and higher storage capacity.
The transistor was far superior to the vacuum tube, allowing computers to become smaller in size, cheaper, reliable and more energy efficient. Though transistor still generated a great deal of heat, it was a substantial improvement over the vacuum tube.
Second generation of computers was also characterized by allowing programmers to specify instructions in symbolic (or assembly) language rather than cryptic binary machine language.
High level programming languages like COmmon Business Oriented Language (COBOL) and FORmula TRANslation (FORTRAN) were also being developed at this time.
Due to the increase in the cost of expanding programming, these machines were expensive to purchase and operate. Such computers were, therefore, mostly found in large computer centres or government/private laboratories with many programmers and support professionals.
Third Generation Computers (1964 to 1971)
The development of Integrated Circuit by Jack Kilby, an engineer with Texas Instruments, in 1958, was the hallmark of the third generation of computers. Punched cards and printouts gave way to devices like keyboards and monitors making it easier for the user to interact with the computer. Computer manufacturers could provide a range of accessories like the cathode ray tube display devices, page printers, consoles etc.
Existence of an operating system allowed the device to run various applications at one time with the central program monitoring the memory.
For the first time, computers were being widely used in business for areas like :
• Accounting
• Payroll
• Billing
• Tracking Inventory, etc.
Third generation computers were substantially smaller and cheaper than their predecessors.
Fourth Generation Computers (1971 to present)
The trend in 1970s was to move from single-purpose but powerful computers towards cheaper computer systems that could support a large range of applications.
A new revolution in computer hardware came about which could shrink the computer logic circuitry and its components using the Large Scale Integration (LSI) technology. Hundreds of components could now fit onto a single chip!
In the 1980s, Very Large Scale Integration (VLSI) squeezed hundreds of thousands of components onto a single chip. This shrinking trend continued and led to the introduction of personal computers (PCs) – programmable machines that are small enough and inexpensive so that these can be purchased and used by individuals. Companies like Apple Computers and IBM introduced very successful PCs.
The IC technology was not only used to construct the processor, but also for the construction of memory. The first memory chip was constructed in 1970 and could hold 256 bits.
Fifth Generation Computers (the Road Ahead)
The fifth generation of computers characterized by artificial intelligence is in the process of development. The goal here is to develop devices that are capable of learning and responding to natural language input. This generation of computers is using new technologies in very
large scale integration, along with new programming languages and will be capable of amazing feats, in the area of artificial intelligence, such as voice recognition.
Advantages and disadvantages of computers
Students in groups should complete this exercise (Arrange these in two columns Advantages and Disadvantages)
If tele-working becomes popular, many people will become cut-off from work mates and the consequent feelings of isolation may lead to depression and other forms of illness.
Without computers many of the facilities which we have become accustomed to would simply be impossible, e.g.
• Access to vast amounts of data via the Internet;
• Rapid and efficient world-wide communication systems;
• Advanced scientific research;
• Space exploration;
• Automatic washing machines;
• Electronic fund transfer.
As things happen more quickly through the use of computers, the pace of life is accelerating at an alarming rate and consequently, stress related illnesses are becoming more prevalent.
Personal data stored in computer systems can lead to loss of privacy.
New jobs are created by I.C.T. such as computer programming, systems analysis, computer manufacturing and maintenance, hardware and software retailing, computer training, etc.
Computerisation of businesses can lead to redundancy and unemployment for some people.
Computers can be used for jobs which humans may find boring, time-consuming, repetitive, or even dangerous. Furthermore, computers don't need sleep, tea-breaks or holidays and they don't go on strike.
Many people are now able to work from home through tele-working systems. People who used to be unable to go to work because of physical handicap, or because they cared for children or elderly relatives at home, have benefited greatly.
The rapid advance of computer technology in all areas of work can lead to loss of job security for many people no matter how qualified they may be.
I.C.T. can provide people with new ways to learn including those with learning difficulties and physical handicaps.
People who become redundant through the introduction of computers need to be re- trained for other jobs.
Businesses which computerize their operation generally become more efficient and consequently more productive. This means that they are able to contribute more to the wealth of the nation and so improve the quality of all of our lives.
6.1. Levels of management:
This refers to a pyramid model of the hierarchy of command in an organization. It is a three tier view that conceptualizes management into strategic management, tactical management and operational management.
The middle level management or tactical management comprises of horizontally into areas of management.
The most common areas are Administration and Finance, Marketing, Human Resources, Information Technology, Research and Development, etc.
In view of this organization structure ISs can be categorized according to that management pyramid;
1. Operational Management (First Line Managers) requires Information Systems capable of capturing transactional data from day to day operations. This called a Transaction Processing System (TPS).
The system should be capable of processing volume of data captured in organizations transactions such as sales system, inventory system, students’ registration system. The data collected by these systems may be deposited into the organizations Database Management System (DBMS) to be used as raw materials for the Middle Level (tactical managers) Management Information System (MIS).
A TPS may be real time or batch based. Real time means data collected is processed immediately for immediate output to aid in a current transaction, e.g. Bank Cashier Terminal Processing System. A batch processing system means data collected is collated together so that it is processed at one go later in the day or another specified time. These systems are easy to automate for they support structured decisions, for example a Bank Cashier Terminal Processing System can be replaced by an ATM. With the power of Internet TPS systems can also be based on Internet infrastructure. An organization can operate a private Internet based TPS where employees can access the organization’s
private Internet accessible database to conduct transactions from different branches of the organization such as bank branches network. This called an intranet. These systems can also be extended further to allow customers and suppliers to for example process their orders or track their supplies. Such as a system is called extranet. Various organizations are also embracing IS systems to provide unique services such as e-commerce, e-ticketing, e-banking, etc.
2. Tactical management: The data collected in the organization DBMS becomes the raw material for producing information for middle level managers. These databases are interrogated by an interface called Management Information System (MIS). Generally speaking an MIS is a system for providing information for managers. It is therefore a general term for an IS. However, specifically MIS refers to an IS for providing information for the middle level of management. It is therefore based on a DBMS that collects data from organization TPS to provide special information depending on the functional management targeted. At this level these MIS may also be called Decision Support Systems (DSS) because the information provided to these tactical managers is meant to aid them in decision making. A DSS is a system that provides information to aid tactical managers in the decision making roles. The decisions supported are semi-structured. They use partial rules automated in the computer system and partly on the manager’s wisdom and experience. Information used in a DSS is taken from TPS and MIS, in addition to this external information may also be incorporated.
With all the information gathered, managers can use models contained within a DSS to look at what might happen if they do certain things. This is a bit like an IF statement that can be changed, scenarios or goal seeking. If a change is made to the figures then the output is increased or decreased.
3. Strategic Management: This is the top most level of management. Their use of information system may not be frequent. However, they need information on exceptional issues of the organization on demand or on the need to know. At some low frequency they may also need regular reports. Such reports are highly summarized and very graphical to allow quick view of the organization at any one point. Executive information systems are used for this purpose. They have very user friendly features such as a dashboard with graphics represent various parameters of interest and allow the CEO to drill down for information and interrogate the report for any finer details they may need. The nature of decisions made by this management is unstructured. They have no clear rules but largely depend on the wisdom and experience of the decision maker. For example a decision on whether to forge a business alliance, how to raise capital, etc. Strategic management may also use Expert Systems to be able to make decisions in areas where they have no adequate expertise. An Expert System is a knowledge-based computer program or artificial intelligence containing expert domain knowledge about objects, events, situations and courses of action, which emulates the process of human experts in the particular domain. In other words, expert system is a computer application that performs a task that would otherwise be performed by a human expert. Expert systems are extensively used in the medical field. For example, there are expert systems that can diagnose human illness, and MYCIN is one of the popular expert systems in medical field. However, Expert Systems can also be used at other levels of management.
7. CHAPTER 2: COMPUTER HARDWARE
7.1. Definition
Hardware refers to the computer’s physical equipment. They include input devices, the processor, output devices, and storage devices. Hardware can also include data communication equipment, also called networking equipment.
7.2. Input Devices
Input Devices are used to enter raw data into the system. They include devices for manual human input (keyboard, mouse, trackball, touch screens) and dde - source data automation (interactive touch screens, magnetic card readers, optical recognition, and voice recognition). Data may be stored for batch processing or processed immediately. Data may be in a form acceptable for another machine or usable by people
7.3. Processor Unit
Processor Unit includes primary storage and the CPU (control unit and arithmetic/logic unit).
The control unit includes instruction registers and control circuits. The control unit (along with the main memory) makes possible the stored program concept of computer operations. The control unit interprets program instructions; control circuits are activated to complete operations and results are stored. The arithmetic/logic unit (ALU) performs all mathematical computations and logical comparisons. Data are transferred as needed from main memory to the arithmetic/logic unit for manipulation and then returned to main memory for additional processing or output.
The CPU physically is a microprocessor that includes the control unit and arithmetic/logic unit mounted on a silicon chip. A multiprocessing operation mode is possible when a computer contains more than one microprocessor.
7.3.1. RISC Vs CISC processors 7.4. RISC versus CISC processors Classification of instruction sets
There are two basic types of instruction sets architectures of processors; complex instruction set computer (CISC) and reduced instruction set computer (RISC).
CISC
CISC is an instruction set design where each instruction in a CISC instruction set is meant to perform a series of operations inside the processor. This reduces the number of instructions required to implement a given program, and allows the programmer to learn a small but flexible set of instructions.The philosophy behind it is that hardware is always faster than software, therefore one should make a powerful instruction set, which provides programmers with assembly instructions to do a lot with short programs. Intel and AMD processors normally use CISC instruction set design.
RISC
RISC chips evolved around the mid-1980 as a reaction at CISC chips. The philosophy behind it is that fewer, simpler and faster instructions would be better, than the large, complex and slower CISC instructions.
However, more instructions are needed to accomplish a task.
An other advantage of RISC is that - in theory - because of the more simple instructions, RISC chips require fewer transistors, which makes them easier to design and cheaper to produce. Finally, it's easier to write powerful optimised compilers, since fewer instructions exist.
RISC vs CISC
There is still considerable controversy among experts about which architecture is better. Some say that RISC is cheaper and faster and therefor the architecture of the future.
Others note that by making the hardware simpler, RISC puts a greater burden on the software. Software needs to become more complex. Software developers need to write more lines for the same tasks.
Therefore they argue that RISC is not the architecture of the future, since conventional CISC chips are becoming faster and cheaper anyway.
RISC has now existed more than 10 years and hasn't been able to kick CISC out of the market and at least 75% today's PCs, workstations and servers processors are based on the CISC architecture. Most of them the x86 standard (Intel, AMD, etc.), but even in the mainframe territory CISC is dominant via the IBM/390 chip. Looks like CISC is here to stay …
Is RISC than really not better? The answer isn't quite that simple. RISC and CISC architectures are
becoming more and more alike. Many of today's RISC chips support just as many instructions as yesterday's CISC chips. The PowerPC 601, for example, supports more instructions than the Pentium. Yet the 601 is considered a RISC chip, while the Pentium is definitely CISC. Further more today's CISC chips use many techniques formerly associated with RISC chips.
So simply said: RISC and CISC are growing to each other.
7.5. Output devices
Output devices produce results of processed data and relay it to the user. The output format can be a hard copy or softcopy. Softcopy output that can be viewed on a monitor or heard over speakers while a hardcopy is a physical or tangible output printed or plotted on paper.
Softcopy output devices include; visual display units and audio output devices. There are several varieties of display units (also called monitors or computer screen). These include CRT monitors and TFT monitors.
CRT monitors are huge and bulky. They consume a lot of office space and electricity and the technology has been phased out. TFT monitors are smaller and flat. They consume less office space and are available in different sizes and technologies.
Hardcopy devices include printers and plotters. Plotters produce their output by drawing. They are mainly used in architectural drawings and with scientific equipments. However, printers have wide application in business for printing out office documents. Printers can be impact or non-impact printers. Impact printers use a hammer mechanism and are therefore noisy but suitable for producing duplicate or multiple documents.
Impact printers are represented by dot matrix printers. They are called dot matrix printers because they produce their output in form of matrix of dots by the hammering mechanism and print ribbon. Such printers are commonly used by banks and other businesses to produce customer statements and other transaction documents such as deposit or withdrawal slips in a bank (as POS printers, also called E-POS (Electronic Point of Sale) printers). Non-impact printers on the other hand are noiseless and use a variety of technologies to produce their print output. Non-impact printers include inkjet printers, laserjet printers, thermal printers and bubblejet printers. Inkjet printers produce their output by use of liquid ink released in small jets from a cartridge. They are the cheapest options for small offices and home use especially for color printing or multi-functions such as copying, printing and scanning. However, ink cartridges print yield is low - some modifications to use continuous ink supply system (CISS) are available that provide an external ink reservoirs for refilling is available, to create high yield and economical output in a commercial setup.
Laserjet printers user laser beams, light sensitive magnetic drum and powdered ink called toner cartridge, with heat roller mechanism to produce glossy and high quality printout. They are expensive but best choice for quality office documents both in monochrome printing and color printing. They may also be available in
sensitive paper and thermal transfer unit. They are commonly used as POS (or E-POS) printers in retail outlets, and ETR printers. However, their print copy fades with time as exposed to light. Bubblejet printers on the other hand are supplied in small portable printers for off-the road print out. They produce their copy by use of inkjet bubbles. Usually the do not need external power for they can be powered by the USB port of the computer or laptop. They are not suitable for commercial application.
7.6. Storage Devices
Storage Devices are divided into primary and secondary storages also called auxiliary storage. Primary storage includes Read Only Memory (ROM) and Random Access Memory (RAM). ROM contains the manufacturer’s firm ware but the RAM provides the computer’s working memory. The secondary storage is used for data that are saved for future processing. Processed data are saved using unique file names to identify the information or program. Common devices include magnetic disk, optical disc, DVD, USB flash drive, and magnetic tape.
7.7. Networking equipment
Data Communication and Networking equipment: These are devices used for interconnecting of computers and data communication. They include modems, network switches, network cards, routers, bridges, LANs and WANs, Wi-Fi, etc.
7.8. Types of Computers
A computer is a programmable electronic device that receives data to process it using some set of
instructions to produce information. There are two basic categories of computers namely, analog and digital computers, but a third category can also be available by combing the two types to create a hybrid computer.
Analog computers are computing or tabulating devices that provide continuous measurement of a quantity or physical matter such as an analog clock, analog microwave, analog weigh scale, etc. These equipment have limited application in business and are actually not included in the day to day conversation about computers.
The digital computer is represent data and signal in a two state electrical circuit; OFF or ON which is translated into two digits 0 or 1 which are referred to as Binary Digits (abbreviated as BITS). This is the modern meaning of a computer device.
Therefore, today’s computer systems fall into one of the following categories:
1. Supercomputers 2. Mainframe Computers
3. Minicomputers or Midrange Computers 4. Microcomputers
Supercomputers:
• Most powerful computer made
• Physically they are the largest
• Process huge amounts of data
• Can house thousands of processors
• Relatively rare because of size and cost.
• Used by large corporations, universities and government agencies.
Mainframe Computers
• Used in large organizations like insurance companies, and banks where many people need frequent access to the same data, which is usually organized into one or more databases.
• Airlines, Government Agencies (Federal Aviation Administration and Census Bureau) track information about large populations, individual tax records, payroll, and more.
• Are being used more and more as specialized servers on the World Wide Web, enabling companies to offer secure transactions with customers over the Internet.
• Many enterprises are connecting personal computers and personal computer networks to their mainframe system. This allows access to the mainframe data and services and also enables them to take advantage of local storage and processing, as well as other features of the PC or network.
• Houses an enormous volume of data (literally billions of records)
• Mainframe can occupy entire rooms or even an entire floor of a high-rise building. Special air conditioning systems are used to keep them cool and on raised floors to accommodate all the wiring needed to connect the system.
Minicomputers
• Abbreviated version of mainframe computers.
• The capabilities are somewhere between mainframes and PC.
• Minicomputers can handle much more input and output than personal computers can.
• Designed for a single user, most are designed to handle multiple terminals.
• Can be used as a server for PC’s Microcomputers
• The microcomputer is “the computer for the masses” and personal computing
• Microcomputers include the following types: Desktop models, including workstations, notebook computers (laptops), Network Computers (netbooks), Mini laptops and Handheld personal computers, PDAs
8. CHAPTER 3: COMPUTER SOFTWARE
8.1. Types of software
Computer software refers to the set of instructions that are used by the computer for its data processing.
Software can be categorized into systems software and application software.
8.2. System Software
System software: refers to a collection of software required by the computer to perform its own internal process. This software includes firmware, operating systems and utility programs.
8.3. Firmware
These are native programs that are loaded to the computer at the point of manufacture and are embedded as a part of the computer basic configuration in Read Only Memory (ROM) chip or its variance equivalent. These programs perform Basic Input Output Systems (BIOS) functions such as performing Power-On Self Test (POST) or Pre-Operational Self Test when the computer is powered on. In absence of an operating system the firmware will load and await further instructions of the system administrator on the location of the operating system. They may also include various system drivers and hardware equipment drivers supplied by equipment manufacturer.
8.4. Operating systems
Operating systems: refers to programs that support the basic functions or operations of a computer system.
Examples of operating systems include Ms Windows, UNX, Mac Os, Novell Netware, etc. These functions including;
i. Booting a computer (i.e. preparing a computer for use by initializing its hardware and software resources)
ii. Providing user interface: or the human computer interface that enables interaction of a computer user with the computer system e.g. Windows Graphical User Interface (GUI) using Windows Icon Menu and Pointer (WIMP) interactions
iii. Managing memory of the computer: It allocates how the computer memory is utilized during processing
iv. Hardware and software interface: The operating system provides a platform to load hardware drivers and help various hardware added to the computer system to interact with the software
v. System resources management (Interrupt request handling): these include all the resources of the computer apart from the memory management. Each resource in the computer is assigned a unique identity code called IRQ that identifies the priority given to that resource when it calls for attention from the processor
vi. Error handling: during processing the operating system responds to errors that may arise such as output device missing, memory overflow, etc.
vii. Security management: The operating system includes access controls and authentication mechanism to ensure the system maintains its integrity and data reliability and is secure from unauthorized access
8.5. Utility programs
These are programs that expand the capacity of the computer by providing other additional services. They include software developers’ tools such as programming languages – compilers, debuggers, linkers, translators, and assemblers; systems tools and accessories such as antivirus, backup and restore, media players, CD burning software, Adobe Reader, Games, etc.
8.6. Application software
These are user programs that have been developed to deliver a specific functionality for what a user does in his or her day to day operations. This means the application software required by the computer depends on who the user is. Accountants need accounting software, statisticians need statistical packages, school needs a school management system, etc. Further application software is categorized according to nature of its distribution. If the package is available as off-the-shelf then it is referred to as application package, examples include Ms Office packages, QuickBooks, SPSS, etc. If it is tailor-made by in-house development of hired or internal team of software developers it is called be-spoke software. Application packages are cheap for they are mass produced but may not be adequate for unique functionalities of an organization.
However, be-spoke software is expensive and many times the developers may choose to package is to sell to other similar organizations.
Depending on the terms of sale, software may also be commercial or open-source. Commercial software is available for sale and cannot be duplicated or altered without the authority of the owner. Such acts of illegal reproduction are referred to as piracy. However, open-source software is free to use and to modify. However, owners of the software may change for some special rights on services such as installation and support. Over the Internet a number of software can also be downloaded as freeware, shareware, demo versions or commercial software. Freeware are absolutely free to use. Shareware are copyrighted and shared free of charge but a donation may be expected or some limitations may exist if you use it regularly, demo versions are commercial softwares given as trial version to use for a period of time or with limited functionality or with a penalty of carrying developers banner ads. However, one is expected to purchase the commercial version after working with the demo version.
8.7. Application Packages Used to Support End-User Computing
These refer to a number of application packages used for office automation and by knowledge workers. They can be classified into;
i. Word processors ii. Spreadsheets iii. Databases
iv. Presentation graphics v. Desktop Publishing packages vi. Photo and Video editors vii. Statistical packages viii. Accounting packages, etc.
9. CHAPTER 4: CONTROLLING INFORMATION SYSTEMS
Data security and controls refers to various threats to data and the counter measures taken to ensure that data is not lost, altered illegally or accessed by unauthorized persons. Although data does not show on the balance sheet as an asset, many companies are totally reliant on the information stored on their PC’s, Laptops and Networks. Electronic data processing involves processing large volumes of data with little or no human intervention. It also concentrated in small storage media that can be easily stolen or misplaced. Computer Based Information Systems are also often connect on the Internet such that unknown persons can remotely connect to an organization's computers without been noted physically.
Here we look at some of the issues to consider when reviewing the security of your computer systems, and some of the compliance issues surrounding data security and data protection.
10.
10.1. Threats to data
As earlier identified due to the nature of electronic data it can face 3 types of threats;
- Loss of data (system unavailability): Possibly due to theft, corruption by virus or system malfunction, power failure, Internet disconnection, etc.
- Unauthorized alteration or accidental alteration (loss of integrity): Such data although may not be said to be lost, the contents are no longer reliable. So the data has lost its integrity.
-Unauthorized access (loss of confidentiality): When data is accessed by unauthorized users such as eavesdroppers, hackers and industrial espionage, the company may lose the benefit of its trade secrets. Many times employees are source of this threat and so persons should be limited to the data that concern the alone and audit trails can be used to track what employees do in their computer systems.
10.2. Administrative controls versus system controls
Administrative controls refers to data security controls that are implemented through the organization administrative framework. It involves policies and procedures about
processing data; such as segregation of duties, insurance, fire and anti-burglary,
authorization of processing, work ethics, and any other practices that enhance safety and
System controls on the other refers to data security control measures that are in-built into the computer system to ensure correct input, correct processing, correct output and security of data stored. Such controls become a part of the computer system design.
10.3. Physical versus logical controls
The controls needed for information systems performance and security, the legal and ethical implications of the control of computer crime and other societal impacts of information systems.
Although data does not show on the balance sheet as an asset, many companies are totally reliant on the information stored on their PC’s, Laptops and Networks.
Here we look at some of the issues to consider when reviewing the security of your computer systems, and some of the compliance issues surrounding data security and data protection.
11.
11.1. Examples of Data Security Controls
12.
PasswordsPasswords are one of the measures which can be used to implement access controls.
However, to be at all effective they should:
be relatively long (i.e. 8 characters or more)
contain a mixture of alpha, numeric and other characters (such as &^”) not be the same for all applications
be changed regularly
be removed or changed when an employee leaves.
13.
Data backup and restoreData backup is an essential process for security and needs to be undertaken on a regular basis. There are a number of points to consider.
14.
Data file locationsIn a network environment some data files might be stored on the server and other data files stored on local drives. In which case separate backups may be required for both the server and one or more PC’s.
15.
Backup strategyThere is likely to be a need for two parallel backup procedures; one to cover a complete systems backup and another to cover the backing up of individual applications’ data files.
16.
Complete systems backupOn a network some form of server backup software should be used to take a complete copy of the network drive(s). This can normally be set to run overnight. However, someone will need to be given responsibility for these procedures -
Key areas to consider include:
training in how to use the backup software, alter backup schedules and change backup file criteria The person responsible needs to be able to:
adapt the backup criteria as new applications are added interpret backup logs and react to any errors notified restore data from backup media
maintain a regular log of backups and where these are stored.
Finally, be aware that some backup utilities only take a mirror image of the hard disc. In this case, the whole of the hard disc has to be restored even if there is a problem with just one file or just one folder.
17.
Applications backupMany accounting and payroll packages have their own backup routines. It is a good idea to use these (as well as full server backup) on a regular basis, and always just before period end, or pay period end, update routines.
18.
Local PCsRemember that some users will have applications data files exclusively on their local drives (such as payroll data for example) and these will all require their own regular backup regime.
19.
Backup mediaThere are about half a dozen different types of backup media available – from the writable CD capable of storing up to 1gb, through the DVD reader/writer (5gb) up to the mighty external hard drives (1000gb). Most server backups will use either use tape cartridges or CD/DVD reader/writers. For more temporary forms of backup, a USB memory stick/pen (1gb) might be considered.
20.
Backup frequencyA cycle of backups should be retained for a period of time (probably going back at least 12 months – but see Backup retention below). Overwriting the same backup disc/tape/cd/dvd day after day is not advised.
21.
Backup retentionBackups should be stored in a variety of locations. Obviously, the safest place is off-site.
Physical backup media can be stored in a separate location, whilst some firms may rent disc space on a service provider’s server, to backup files to.
Issues such as how long certain type of records, accounting records for example, need to be kept for, should be borne in mind.
22.
Backup media degradation/decompositionBackup media degrades and the data decomposes over a period of time.
DVD’s are particularly sensitive to light (i.e. they are photosensitive) for example, so ensure that they are stored in a dark environment.
RW media is noted as being particularly prone to degradation, and should not be relied upon for long-term storage.
Backups should be checked on a regular basis for signs of digital decomposition.
23.
Restoring dataAs with backup, there are a number of issues to consider.
Total systems restore. This can be a complex procedure in a network environment and may require specialist network engineers to provide assistance.
Application restore. We recommended above (see Applications backup) a separate cycle of backups to cover individual applications. If it is necessary to restore the whole application from these backups, then the restore utility within the package concerned needs to be used and the correct backup media loaded.
Individual data file(s) restore. These are generally less complex, but nevertheless care is needed. If the required data files are on the server backup then the restore utility will need to be used, the correct backup media loaded and the file or files to be restored identified.
24.
25.
Virus/Spam protectionThe prevalence of e-mail viruses and unsolicited spam means that software is required to filter these items out of the system. This software will require regular updating, along with all relevant on-going software security patches that need to be applied to the operating and applications software. Additional network security in the form of firewall software is also required to protect the network from unauthorised access and potential network attacks.
26.
All employees should know and understand the firms’ security procedures and the consequences of abusing these. You might wish to refer to our factsheet which sets out a model internet and e-mail access policy. Staff dealing with personal data also require training in the principles of data protection and good information handling practices
28.
Compliance issuesMost businesses process personal data to a greater or lesser degree. If this is the case, then notification under the Data Protection Act is required. That will then mean on-going compliance with the principles of information handling and information security. We can help you with this process to ensure compliance.
Control and Management Issues
Transaction processing systems are the backbone of any organization’s information systems.
29.
Business Resumption Planning• It is the process of anticipating and providing for disasters. A disaster can be a flood, fire, earthquake, intentional damage, labor unrest or erasure of an important file.
• Focus on maintaining the integrity of the corporation information and keeping the information system running until normal operations can be resumed.
• Identify potential problems and prepare for the disaster.
30.
Disaster Recovery• The implementation of the business resumption plan.
• The primary tools are backups for hardware, software, databases, telecommunication, and personnel.
• Keep a backup copy of software and database to a remote location in a safe, secure, fireproof, and temperature and humidity controlled environment.
• Always train backup personnel in case employees leave the company.
31.
Transaction Processing System Audit• Auditing a TPS system, is an attempt to answer three basic questions:
• Does the system meet the business need for which it is developed?
• What procedures and controls have been established?
• Are the procedures and controls being properly used?
• An internal audit is conducted by employees of the organization and an external audit is conducted by an outside firm.
• The auditors inspects all programs, documents, control techniques, the disaster plan, insurance protection, fire protection, and other system management concerns such as efficiency and effectiveness of the disk and tape library.
The audit trail allows the auditors to trace any out from the computer system back to its source documents.
32. CHAPTER 5: Ms Word
32.1. Introduction to Ms Word
Microsoft Word 2007.doc
33. CHAPTER 6: Ms Excel
MS Excel.pdf
