Transcript web history

Internet History
• Internet made up of thousands of networks
worldwide
• No one in charge of Internet - No governing
body
• Internet backbone owned by private
companies
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Looking at the Net
Taken from: http://www.cio.com/WebMaster/sem2_net.html
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Understanding the Map
• Computers use TCP/IP to communicate
(Transmission Control Protocol/Internet
Protocol)
• Computers use client/server architecture
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Internet Providers:
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Research and Educational Institutions
Government and Military Entities
Businesses
Private Organizations
Commercial Providers
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Internet Protocols
• Email (Simple Mail Transport Protocol)
• Telnet (Login to remote host computer)
• FTP (File Transfer Protocol) - transfers
files between server and client
• HTTP (HyperText Transfer Protocol)
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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
(2) OCLC Office of Research, “June 1999 Web Statistics” Web
Characterization Project
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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:
HyperText Transfer Protocol
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HTTP
• Hypertext - means of information retreival
• Contains links that connect to other
documents
• Links selected by user
• Virtual “web” of connections
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HTTP (cont)
• Produce HTTP through HTML
• HyperText Markup Language
• Way of writing or creating with “tags”
added to tell information
– i.e. <b> Bold </b> yields Bold
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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
computers and platforms
• “Universal readership”
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Web Popular Because:
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Easy to use
Easy to navigate
Combines words, graphics, sound, video
Easy to Publish
Plethora of information
Reach larger audience
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Summary: Web vs. Internet
• What is the relationship between the web
and the Internet?
• The Internet contains physical components
– computers
– networks
– services
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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
• Web - set of protocols and tools that let us
share information with each other
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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
• Browser compatibility problems can cause web page problems
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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
Resource Locator. All publicly accessible websites collectively
constitute the World Wide Web.
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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,
renders the page content according to its HTML markup
instructions onto a display terminal
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• 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 Mosaicinfluenced Netscape Navigator in 1994, which quickly became the
world's most popular browser, accounting for 90% of all web use at its
peak (see usage share of web browsers).
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Two Basic Approaches to
Searching
(although not really “basic”)
• Search Engines
• Subject Directories
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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 (some also utilize submissions and
administration)
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Which Search Engine?
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Yahoo
Altavista
Excite
Google
NorthernLights
Hotbot
Infoseek
See Handout - “The Little Search Engine that Could”
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