Internet History
• Internet made up of thousands of networks worldwide
• No one in charge of Internet - No governing body
Looking at the Net
Understanding the Map
• Computers use TCP/IP to communicate (Transmission Control Protocol/Internet Protocol)
Internet Providers:
• Research and Educational Institutions • Government and Military Entities
• Businesses
Internet Protocols
• Email (Simple Mail Transport Protocol) • Telnet (Login to remote host computer) • FTP (File Transfer Protocol) - transfers
files between server and client
History
• WWW or Web or W3 includes all information, text, images, audio, video, and computational services that are accessible from the internet
• July 8, 1999 Nature - approximately 800 million pages of publicly accessible information(1)
• Web continues to grow, tripling in size over the past two years(2)
(1) Steve Lawrence & C. Lee Giles, “Accessibility of Information on the Web,” Nature 400 (July 8, 1999), 107
WWW
• System of Internet servers that support hypertext to access several Internet
protocols on a single interface
• Almost all protocols accessible on Internet are accessible on web (email - FTP - Telnet - etc)
• In addition, WWW own protocol:
HTTP
• Hypertext - means of information retreival • Contains links that connect to other
documents
• Links selected by user
HTTP (cont)
• Produce HTTP through HTML • HyperText Markup Language
• Way of writing or creating with “tags” added to tell information
More History
• Internet initially conceived in 1989 by Tim Berners-Lee at CERN (European Particle Physics Lab in Switzerland)
• Needed a wide variety of information to be shared and distributed to many different
Web Popular Because:
• Easy to use
• Easy to navigate
• Combines words, graphics, sound, video • Easy to Publish
Summary: Web vs. Internet
• What is the relationship between the web and the Internet?
• The Internet contains physical components
Web vs. Internet
• The Internet connects thousands of
computers across the world, but it is the web that allows communication to occur • Web - abstraction and common set of
services on top of the Internet
Browsers
• What is web browser?
browser: a program used to view HTML documents
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web
The first web browser was invented in 1990 by Sir Tim Berners-Lee. It was called WorldWideWeb (no spaces) and was later renamed Nexus.
• Netscape Navigator (Communicator)
– Product of Netscape (Now owned by AOL) – Originally was dominant
– Multi-platform (all operating systems) • Internet Explorer
– Product of Microsoft
– Current Dominant Browser
– Not available for all operating systems
Browsers
• What is web browser?
browser: a program used to view HTML documents
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web
The first web browser was invented in 1990 by Sir Tim Berners-Lee. It was called WorldWideWeb (no spaces) and was later renamed Nexus. • What is website?
• web site: a computer connected to the internet that maintains a series of web pages on the World Wide Web;
• A website, is a set of related web pages containing content such as text, images, video, audio, etc. A website is hosted on at least one web server, accessible via a network such as the Internet or a private local area network through an Internet address known as a Uniform
Web Page
• A webpage is a document, typically written in plain text interspersed with formatting instructions of Hypertext Markup Language (HTML, XHTML). A webpage may incorporate elements from other websites with suitable markup anchors.
• Web pages are accessed and transported with the Hypertext Transfer Protocol (HTTP), which may
optionally employ encryption (HTTP Secure, HTTPS) to provide security and privacy for the user of the webpage content. The user's application, often a web browser,
• The first web browser was invented in 1990 by Sir Tim Berners-Lee. It was called WorldWideWeb (no spaces) and was later renamed
Nexus.
• In 1993, browser software was further innovated by Marc Andreessen with the release of Mosaic (later Netscape), "the world's first popular
browser",[5] which made the World Wide Web system easy to use and
more accessible to the average person. Andreesen's browser sparked
the internet boom of the 1990s.[5] The introduction of Mosaic in 1993
– one of the first graphical web browsers – led to an explosion in web use. Andreessen, the leader of the Mosaic team at NCSA, soon started his own company, named Netscape, and released the
Two Basic Approaches to
Searching
(although not really “basic”)
• Search Engines
What are Search Engines?
• Designed to assist you in searching through the enormous amount of information on the Web
• No single search tool has everything
• Each engine is a large database which utilizes different search techniques and tools (spiders or robots) to build indexes to the Internet
Which Search Engine?
• Yahoo • Altavista • Excite • Google
• NorthernLights • Hotbot
• Infoseek
