User interfaces
Command line interface and Graphical user interface
•The way in which users communicate with the computer is called an 'interface’.
•The interface is what we use to give the computer commands. There are two types of operating system interfaces:
•Command Line Interface (CLI)
•Graphical User Interface (GUI)
•Touchscreen Interface (POST WIMP)
Types of Operating System
Interfaces
Command line interface (CLI)
# A command line interface is an older style operating system where users type in commands using keyboard.
# Command Line Interface's do not make use of images, icons or graphics.
# Because they use no graphics they require very little computer power.
# There are over 270 different commands that can be entered at the command prompt. Commands have to be entered precisely without spelling mistakes or else the operating system will return an error.
# Remembering commands and the exact way to enter them can be difficult and so Command Line Interface Operating Systems are considered hard to use.
Keyboard used to... Enter commands into... A command prompt
command What it does
copy Copies files from to another location
del deletes one or more files
format Deletes all the data on a hard disk
md Creates a new folder
rename Renames a file or folder
Examples of some commands
Graphical user interface (GUI)
GUI allows the user to interact with computer using pictures or icons rather than having in type in a number of commands
GUI's are visual (graphical) interfaces and they are more popular than CLI's because they are very easy to use. The graphics do need more computer power however.
Instead of typing in commands, the user can use a mouse to point and click objects on the screen.
For example :A user can erase a file by right clicking and then selecting delete.
GUIs use various technologies One of the most common is WIMP (Windows , Icons , Menus ,Pointers)
Windows
Icons
Menus Pointers
The user can divide the screen into separate areas known
as 'windows'
Icons are 'symbols' or small images / graphics that are used
to represent files and commands.
Pointers are little arrows that you move across the screen by directing your mouse.
These allow users to select functions from a list.
Touchscreen Interfaces (aka Post-WIMP Interface)
Portable devices such as mobile phones, PDA's and tablets (e.g.
iPad) use interfaces similar to a GUI (WIMP) where icons and menus are used to input commands.
However, because these devices don't have room for a mouse, the way in which the icons and menus are used is different.
Features available on POST-WIMP interfaces are highlighted in the table below:
Pinching This is where you pinch your fingers together across a touchscreen to zoom into an image, application or document on your device. You can also move
your fingers apart to zoom out
Rotating This is where you use two fingers - one finger moves up while the other finger moves down the touch screen to rotate an object
Who would use each type of interface?
CLI GUI
Somebody who needs to have direct communication with a computer to develop new software like programmers
End user who doesn’t have any great knowledge of how the computer works
How to remember the difference between Command Line and GUI operating systems.
1. Can you use a mouse to control a pointer? YES
2. Can you select and click icons and menu options? YES Then you are using a GUI
1. Can you use a keyboard to enter typed commands? YES 2. Can you use a mouse to control a pointer? NO
3. Can you select and click icons and menu options? NO Then you are using a COMMAND LINE INTERFACE
1.4 Types of computer
Types of Computers
Computers allow us to perform many different tasks from gaming to complicated calculations. Computers range from very large to very small and it is estimated that there are over 1 billion of them in use around the world.
There are many different types of computers and people often choose which type they use based on what sort of tasks they want the
computer to carry out. This section covers the main types of modern computers including:
• Personal computer
• Laptop
• Tablet computer
• Smart phone
• Smartwatches
• Mainframe computers
1- Personal Computer (Desktop PC)
Internet access is more stable
2- Laptop
2- Tablets
Some of the typical features of tablets :
• High –definition, anti- glare displays
• Font –and back-facing cameras
• Lower weight and longer battery life than laptops
• Bluetooth connection to printers and other devices
• Flash (solid state) memory and cloud storage to back up
• Sensors to carry out the following functions :
a)proximity sensors to detect of the device is close to (for example) the car
b)accelerometer ,which detects movement and orientation of the device c)can use sophisticated speech –recognitions systems(such as Siri)
• Some of the latest tablet devices have been designed as a hybrid between tablet and smartphone which have slightly smaller screens than tablets
• All of the features of a normal phone are available with some of the features of tablet
What is Phablet ??
Smartphone
Uses of Smart phones:
# •The uses of smart phones are very similar to that of
tablets. For example: Internet access (both on wireless and using 3G/4G)
•Multimedia (video, games, music etc)
•Running apps
•Making phone calls and messages
•Send/receive emails
•Voip – telephone network
Some smart phones have small physical keyboards.
New generation of smartphones will use touch screens with OLED technology .
What is Li-Fi??
➢ A type of wireless connection that can be up to 100 times faster than Wi-Fi.
➢ It Is similar to wi-fi except communication uses visible light rather than radio waves
Advantages of Li-Fi:
- Higher data transfer rate
- More secure (stop internet ‘piggybacking’, unauthorized use of the internet connection) - Can be used on flights since it doesn’t use radio
waves.
Advantage Disadvantage
Very small in size and lightweight Small screens make pages difficult to read
Can use them to make a phone call and to connect to the internet
Small keyboard make things in more difficult
They can be used almost everywhere Web browser and photography can drain the buttery quickly
They have hundreds of apps Memory size in most phones isn’t very large
They have reasonable battery life Not all websites are compatible with smartphone operating systems
Much easier to lose smartphone Data transfer rate is slower
Smartwatches
• It is a mini-computer that allows users to wear on their wrists.
• It offers an OLED technology
• It has an ability to link to smartphones using Bluetooth technology
• It uses a touch-screen technology
Smartwatches have the following functions:
Internet connectivity
Ability to make and take phone calls
Messaging via text or video
Weather forecasts
Fitness and health monitoring capability
GPS
Advantage Disadvantage
• They are even more convenient than
smartphones since the technology delivers notifications straight to the user’s wrist
• They are very easy to use for monitoring fitness and health regimes
• They are large and bulky which make them uncomfortable to wear
• They tend to be unattractive in design
Mainframe computers
It is a term used for a large , very powerful , computer system .
Their main purpose is to run commercial applications, such as banking and insurance , where huge amount of data need to be processed every day
The main features of mainframe computers are:
➢ They can have several CPUs
➢ They have very fast processor speeds
➢ They can support multiple operating system
➢ They have amounts of storage capacity
➢ They have huge internal memories
➢ They operate using time sharing or batch processing
1.5 Impact of emerging
technologies
New technologies
"New technologies are those that are currently being developed or will be developed in the next 5 to 10 years, and which will alter the business and social environment."
•The technologies (and their impacts on everyday life) that we are going to focus on
•Artificial intelligence
•Vision enhancement
•Robotics
•Quantum cryptography
•Computer assisted translation
•3D and holographic imaging
•Virtual reality
1. Artificial intelligent (AI)
This is a computer science that is focused on creating computer systems that simulate human intelligence.
The term was first used in 1956 by a computer scientist at the
Massachusetts Institute of Technology (MIT) who was focused on trying to make computers behave like humans
Many fingerprint identification systems falsely reject a person’s fingerprint . Why ??
The solution is AI using something called Dynamic profiling
A person doesn’t have to worry about getting their finger in exactly right place every time on the scanner.
Facial recognition systems have the same problem ! Why ??
What is the solution ??
New systems use AI to learn from scanning a number of faces and can pick out these soft biometric changes.
Vision enhancement
There are two types of vision enhancement system:
Low –vision enhancement systems (LVES) Night vision enhancement (NVE)
Low –vision enhancement systems (LVES)
It use video technology through a headset connected to computer .
The system allows images to be projected in front of the eyes.
This effectively brings the objects closer for examination by the user of the system
Night vision enhancement (NVE)
It amplifies infrared light and visible light so than an image can still be seen in apparent darkness.
Example : the military use this technology to carry out surveillance at night
How it works?
A dim light source is captured
Passed through an image intensifier
tube
It convert light into electrons
These electrons pass through another tube where they are amplified
to produce several times the original number of
electrons The screen at the end of
the tube is coated in phosphor dots that glow
when electrons collide with them
This is an image that is clearer than the original
3. Robotics
Robots are used to perform a wide range of physical tasks.
They are either automated (controlled by a computer chip) or manually controlled by a human.
There are 4 different types of robots:
Manufacturing robots (used to perform repetitive tasks such as welding)
Carrier robots (used by the military to carry heavy loads over dangerous terrain) Domestic robots (used in homes to perform cleaning tasks such as vacuuming) Exploration robots (used to visit and send images from places such as Mars)
One application is the use of drones
These are unmanned flying devices that are used of both the military and civilians
The military have used drone in reconnaissance missions.
4. Quantum cryptography
Quantum cryptography (encryption) is an emerging technology that allows messages and data to be sent with complete privacy.
Note: Encryption is where digital data and files are scrambled so that only authorized people are allowed to read it.
Unauthorized people attempting to read the data would see illegible nonsense instead of the real information.
Older methods of encryption were based
around mathematics but quantum cryptography uses physics instead.
In quantum cryptography, messages are encrypted using photons.
These are tiny packets of light.
Older encryption methods use complex math.
Quantum cryptography secures data using physics.
5.Computer –assisted translation(CAT)
CAT is where a human translator uses computer software to help in the translation process.
CAT uses two tools :
1- terminology databases: linguistic databases that grow and ‘learn’ from translations being carried out
2- translation memories : these automatically insert known translations for certain words , phrases or sentences .
All CAT software needs some post- editing by the user to remove errors from the translation process. And still more accurate that existing free online translators
6. 3D and holographic imaging
This is a technique where images are made to appear three- dimensional and to actually have depth.
The technology involves the use of :
• A source of laser light
• Interference of light
• Light diffraction
• Light intensity recording
1- splitting a laser beam
2- first half called (object beam)->reflected off the object on to a photographic plate
3- second half called(reference beam)->reflected off a mirror and on to the same photographic plate
plate
Holograms have the following applications:
Engineering design (CAD)
Architecture
Medical imaging
Cinema
Gaming
Advertising
Holographic television
7. Virtual reality
Virtual reality is where computers are used to create an artificial environment that users can interact with as if it were real.
• Virtual reality is not really meant for gaming purposes. It is used for more serious purposes such as:
• Allowing architects to walk around a virtual version of their design (this gives a better idea of what the finished building will look like)
• Training soldiers in combat (flight simulation, battlefield simulation)
• Training surgeons (virtual patients can be operated on to provide experience to trainee surgeons).
Other areas for VR:
Fashion (example : to do fashion shows before doing the real one)
Heritage
Business (example : training courses)
Sport(example :improve skills )
Media (example : special effects in films