Transcript 3-1note

3-1 note
The Internet—
More Than Just the WWW
FOCUS QUESTION
• What impact has the Internet and the World
Wide Web had on the world?
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ARPANET
• ARPANET was developed in the 1960s by U.S.
Department of Defense.
• The U.S. Department of Defense created
ARPANET (Advanced Research Projects Agency
Network) to withstand nuclear attacks and
natural disasters.
• ARPANET was first used to share scientific and
engineering information.
• ARPANET split into two parts in 1983
– ARPANET for research
– MILNET for military and defence agencies
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NSFNET
• ARPANET was not fast enough by mid1980s.
• National Science Foundation (NSF) created
new high-speed network called NSFNET.
• There were two objectives to NSFNET:
– 1. To interconnect supercomputing centres
to share resources
– 2. To connect academic and research
centres to share information
• NSFNET replaced ARPANET in the early
1990s.
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The Internet As We Know It
• More individuals purchased PCs in the late
1980s and early 1990s.
• NSFNET served only academic users.
• Demand for Internet access drove
telecommunication companies to offer
service to individuals.
• Companies like Bell Canada, AT&T, and
Nortel built high-speed backbones and new
networks that used the same protocols as
the NSFNET
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TCP/IP
• Transmission Control Protocol/Internet
Protocol (TCP/IP) are protocols, or rules,
for transmitting information that have to be
followed. TCP/IP is
– free
– language of the Internet
– throughout the 1980’s and 1990’s its used
became widespread and the Internet grew
rapidly as a network of many networks
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ISP’s
• Businesses or personal users could set up
Internet accounts with many
telecommunication companies and
INTERNET SERVICE PROVIDERS companies that provide users with access
to the Internet
• During the later 1980’s and early 1990’s,
the most popular uses for the Internet were
e-mail and file sharing
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QUICK BYTES
• INTERNETWORKING - the process of linking a
collection of networks. This term is where the
Internet got its name. The term Internet was
officially adopted in the early 1980’s. Today it is
more commonly referred to as the Net
• SUPERCOMPUTING - supercomputers are
mainframe computers that are capable of very
fast processing. Used for tasks such as
worldwide weather forecasting, oil exploration
and weapons research
• PROTOCOL - an agreed-upon format for transmitting
data between two or more devices.
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Internet vs. World Wide Web
• There is a difference!
• The Internet is a collection of networks and
computers and storage devices linked by
cables and/or satellites.
– Many types of data travel over the Internet.
– One type is the World Wide Web hypertext
document.
• The World Wide Web is a collection of
hypertext documents stored in computers
connected to the Internet.
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World Wide Web
• The creation of the World Wide Web, along with
the development of web browser applications led
to huge growth of Internet and its use.
• The World Wide Web is a collection of millions of
hypertext documents, most often written in a
web authoring language called HTML (Hypertext
Markup Language). The browser follows rules
and knows how to translate codes using HTTP
(Hypertext Transfer Protocol).
• The Web is governed by W3C (World Wide Web
Consortium).
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World Wide Web Consortium
(W3C)
• The four goals for the WWW:
– 1. Make it available to everyone.
– 2. Make it accessible by any device.
– 3. Use it for more than searching, browsing,
and viewing information.
– 4. Make it safer, more trustworthy, and
confidential.
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Navigating the Web
• Navigating the Web requires a web browser. A
browser is a program that interprets hypertext
documents and displays them.
• Tim Berners-Lee created the first web browser in
1989.
• After NCSA Mosaic was released in 1993, free of
charge, the number of web users increased
dramatically. It was eventually replaced by
Netscape Navigator.
• Modern browsers include Microsoft Internet
Explorer and Mozilla Firefox.
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Hypertext Document Features
• Hypertext documents contain hyperlinks.
These hyperlinks lead to other pages or
another part of the same page. The cursor
often turns to a hand when you put your
mouse on top of a hyperlink.
• Hypertext documents are identified by an
address called a URL (Uniform Resource
Locator).
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• What Is a Web Site?
• Every Web site has a unique address, or uniform resource locator
(URL), that includes a three-letter extension that identifies the
type of site.
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Purpose of Websites
• There are three general categories for the purpose of a website:
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1. Information oriented – these websites are used to provide
information to the public. They could be a personal web site,
government information, publicity, or other type of informative space.
Resources IconAn example:
http://www.recycle.nrcan.gc.ca/default_e.htm (A government of Canada
recycling information site)
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2. Operational – these are e-business websites that allow users to purchase
product and services.
•
Resources IconAn example: www.futureshop.ca (A Canadian electronics
retailer)
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3. Campaign - these types of websites will promote a specific cause
or publicity campaign.
Resources IconAn example: http://www.madd.ca/ (Mothers Against
Drunk Driving Canada)
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Structural Foundations
• Infrastructure is the structural foundation
that enables technology to work.
• Communication satellites are critical for
sharing information.
• Fibre optics are also critical to sharing
information. Fibre optics carry information
via light pulses along
ultra-thin glass
fibres.
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WORK! :)
– go to site
– Do:
– - Investigate IT
– - Internet questions
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