Internet and World Wide Web

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Announcements
• Dr. Gerald Urquhart
• Developed LBS 126
Internet and World Wide Web
• Which came first - Internet or WWW?
The Internet
• Internet is a network of interconnected
computers that is now global
• Internet born in 1969 - called ARPANET
• 1969 ARPANET was connection of
computers at UCLA, Stanford, UCSB,
Univ. of Utah
State of computers?
• What was the state of computers in the late
1960s and early 1970s?
Computers late 60s & 70s
• No Personal Computers – all
large mainframe computers
in late 60s
• Mid 1970s – initial personal
computers
– Altair: Box with blinking
lights
• Late 1970s – Apple 2, first
usable PC
Personal Computing?
• Just a box with
blinking lights
• Not where
Networking/ Internet
was being developed
Internet - 1970s
• 1972 - Telnet developed as a way to connect to
remote computer
• 1972 – Email introduced
– 1977 - U. Wisconsin has first “large” Email system 100 users
• 1973 - ARPANET goes international
• 1973 - File Transfer Protocol (FTP) established
State of computers?
• What was the state of computers in the early
1980s?
Computers 1980s
• 1981 – IBM PC
• 1984 – Apple Macintosh
• 1986 – Modem becomes option on PCs
Internet - 1980s
• 1984 - Domain Name Server introduced
– allows naming of hosts, no longer numeric
• 1986 - NSFNET created
– in 1990, becomes backbone of modern Internet
when ARPANET is decommissioned
– Completely privatized by 1995
– 56 K interconnection initially, increased rapidly
Barry M. Leiner, Vinton G. Cerf, David D. Clark, Robert E. Kahn, Leonard Kleinrock, Daniel C.
Lynch, Jon Postel, Larry G. Roberts, Stephen Wolff. A Brief History of the Internet. Internet Society.
http://www.isoc.org/internet/history/brief.shtml
Internet Timeline
NSF Net
Internet 1990s
• 1991 - Tim Berners-Lee releases World Wide Web!
– TBL is computer programmer at CERN, a physics lab in
Europe (new book Weaving the Web by TBL)
• 1993 - Mosaic (becomes Netscape) designed by
graduate students at University of Illinois
– first point-and-click browser
– later developed into Netscape Navigator
• These are the two most significant events in the formation of the WWW
Internet 1990s
• 1991 - Tim Berners-Lee releases World Wide Web!
– TBL is computer programmer at CERN, a physics lab in
Europe (book Weaving the Web by TBL)
• 1993 - Mosaic (becomes Netscape) designed by
graduate students at University of Illinois
– first point-and-click browser
– later developed into Netscape Navigator
• These are the two most significant events in the formation of the WWW
World Wide Web
• Via Internet, computers can contact each
other
• Public files on computers can be read by
remote user
– usually HyperText Markup Language (.html)
• URL - Universal Resource Locator - is
name of file on a remote computer
• http://www.msu.edu/~urquhar5/tour/active.html
HTTP
• World Wide Web uses HTTP Servers, better
known as web server
• Receive HTTP type request and send
requested file in packets
Web Browsers
• Mosaic (1993) was first point-and-click
browser
• Web browsers are the software we use to
view web pages
• Netscape Navigator and Internet Explorer
are most popular
• Netscape Navigator was original, but
Microsoft leveraged IE on market
State of computers?
• What was the state of computers in the early
to mid 1990s?
Computer History – 1990s
• Windows 95 GUI made computing easier
for PC-bound masses
• Windows 95 + Internet (AOL, others) 
Huge increase in number of home PCs
• Computer on every desk in workplace
Universal Resource Locator
http://www.msu.edu/~urquhar5/tour/active.html
http://
/~urquhar5/tour/active.html
identifies type
of transfer
File Location on Remote Computer
www.msu.edu
Domain Name name of remote computer
21st Century – File Sharing
• Internet allowed sharing of simple
information
• FTP was initial file sharing system, but a bit
hard to use
• WWW advanced type of info allowed, but
not designed for file-sharing
• Napster, KaZaA, Morpheus and LimeWire
are file-sharing.
Napster
• Napster was a music sharing community
• Used a central server to catalog who had
what
• This central server violated music industry’s
copyrights
• Napster now screens transfers to see if they
are copyrighted material
Peer to Peer
•
•
•
•
•
Peer to Peer (P2P) file sharing
LimeWire is good one
KaZaA is faster and more advanced
Kazaa Lite is preferred by many
Morpheus is modified KaZaA for Music City
Network – really messed up these days
• Each person has a “node” that advertises his or her
files
• Supernodes – compile lists of what nodes have
Collapse of the Information Economy
• Huge economic growth in late 1990s was
due to “prospecting” on up-and-coming
Internet companies
• Most were never profitable
– Amazon.com just posted its first Annual Profit
(2003) since going public in 1997!
• Major Internet Backbone Providers
(Worldcom, Global Crossing) are struggling
What is WWW?
• Via Internet, computers can contact each other
• Public files on computers can be read by remote
user
– usually HyperText Markup Language (.html)
• HTTP - HyperText Transfer Protocol
• URL - Universal Resource Locator - is name of file
on a remote computer
• http://www.msu.edu/~urquhar5/tour/active.html
How to make a web page
• Define the two basic steps required in
making a web page.
Two Basic Steps
• Create an HTML File
• Upload file to server
– Saving to P: drive eliminates this step
.html
• Web documents are text files with .html
extension
• These text files have HTML “tags” in them
HTML Tags
• Each opening HTML tag has a closing
HTML tag that matches it.
– <P> for begin paragraph is followed by </P>
for end paragraph
– <P> goes at beginning of paragraph
– </P> goes at end of paragraph
Example of Tags
• <P>Here is the paragraph about
something</P><P>Here is the second
paragraph</P>
What it will look like:
Here is the paragraph about something.
Here is the second paragraph.
Essential HTML Tags
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•
•
•
•
•
<HTML> begins HTML document
<BODY> begins body of document
<H1>Here’s a header in big type</H1>
<P>Here’s a paragraph</P>
</BODY> ends body
</HTML> ends HTML document
Browser Output of Page
If you opened that page in Netscape Navigator, it would look
like this:
http://www.msu.edu/course/lbs/126/lectures/viewsource.html
Here’s a header in big type
Here’s a paragraph
View Page Source
• Using “View Page Source” allows you to
see the HTML behind a page
• When we get into advanced HTML pages,
this can be really important for learning
how someone did something
• http://puffin.bird.audubon.org/
File Transfer Protocol
• FTP Program (also called FTP client) used to
transfer files from your computer to your public
web directory housed on the MSU computers
• WS_FTP LE is a good, free FTP program
• In MSU Labs, can directly save stuff in your AFS
space, on the P: drive, in the web directory
Your personal web space
• Http://www.msu.edu/~pilotname/index.html
• Three steps:
– Make your pilot web space public (in advanced
features)
– Create a file named index.html
– Use FTP to transfer a file named index.html into your
web directory
Netscape Composer
• Netscape Composer allows WYSIWYG
(what-you-see-is-what-you-get) editing of
web pages
• Controls similar to Microsoft word – font
formatting, colors, etc.
Macromedia Dreamweaver
• Excellent Site Building Tool
• Allows organization of files, ftp, and
WYSIWYG editing all-in-one
Microsoft Front Page
• All-in-One program like Dreamweaver
• Uses “proprietary tags” that can’t be read by
some browsers (Netscape)
• Uses non-standard HTML, style sheets, etc
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