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INTRODUCTION TO THE INTERNET Briefly describe the history of the Internet
Explain what is needed to get on the Internet
Describe generally what an Internet Service Provider does
Describe the function of a browser
Describe how to search the Internet
List and describe the non- web services of the Internet
INTERNET????
A global network connecting millions of computers
J.C.R, Licklider of MIT – first proposed a global network of computers in 1962.
Leonard Kleinrock of MIT & later UCLA developed theory of packet switching (basic internet connections)
Ray Tomlinson – e-mail
HISTORY OF INTERNET
The Internet exploded into the public consciousness in the mid 1990s
Approximately the Internet grew from 72 million in 2000 to 162 million in 2002
E-commerce is growing rapidly.
Tim Berners-Lee is arguably the pivotal figure in the surging popularity of the Internet
THE INTERNET AS PHENOMENON
GETTING START
The Internet Service Provider and the Browser An internet user needs
• a computer • a modem (dial-up, cable or DSL) • a network connection • the related software • an Internet Service Provider (ISP) • Browser
An ISP provides the server computer and
software to connect to the Internet
The browser in action
A browser is software used to explore the Internet
Microsoft Internet Explorer (IE)
Others like Netscape, Opera and Mozilla are available.
Uniform Resource Locator (URL)
URL is the address window just below the toolbar buttons will usually contain a Uniform Resource Locator (URL) which is the unique address of a web page or file on the Internet
http://www.intel.com/pressroom/index.asp
Protocol Host computer address (Domain)
path, directory, file name
HTTP (Hyper Text Transfer Protocol) communicating by using links
– the clickable text or image that transport a user to the desired web site
Domain name
- the address of the site’s host computer. - “com” called top-level domain and represents the
purpose of organization or entity.
“com” – commercial “edu” – education “gov” – government “org” – organization “net” - networking center
Wireless Internet Access
People using mobile handheld devices to access the Internet
Examples: text pagers, personal digital assistants (PDAs), pocket computers and even web-enabled cellular phones
Many wireless access providers use the Wireless Application Protocol (WAP) to convert web pages into a format that is more compatible with the limited capabilities of handheld devices
Search Engine
A search engine is software, usually located at its own web site, that lets a user specify search terms; the search engine then finds sites that fit those terms
A browser usually offers links to one or more search engines, or a user can simply link to the site of a favorite search engine
Example : a. Yahoo b. Altavista c. About d. AllTheWeb e. Google f. Lycos
A selection of Internet Search Tools Directories
About Human experts, called guides compile
directories organized around specific topics
Yahoo! Well-organized categories let the user switch from browsing to searching in a certain area;
but finds only keywords, not any word on a site.
AlltheWeb Fast; supports a large number of languages; can
limit result to specific domains.
AltaVista Very fast; indexes every word on every page of every site; searches Usenet too; excellent for
custom searches.
Google Result raked by algorithm based on number of
links from other pages.
HotBot Fast; unique search options let you restrict
searches; very comprehensive; excels at finding current news
Lycos Numerous search options, a comprehensive
directory, and good returns on simple searches.
NON-WEB SERVICES OF THE INTERNET
1. Newsgroups
2. File Transfer Protocol (FTP)
3. Telnet
4. E-mail
1. Newsgroups
Usenet – an informal network of computers Allows posting and reading of messages Typically focuses on specific topics Requires a newsreader
Some are moderated Messages sent to a moderator, who determines
whether the message is appropriate Prevents users from attacking other members and
prevents inappropriate material from being posted
2. File Transfer Protocol (FTP)
A protocol for transferring files among computers.
FTP servers maintain collections of downloadable files Downloading can often be done anonymously,
without logging in
Many FTP servers can be accessed through Web browser
3. Telnet
A protocol that allows remote users to log onto a host computer. Users use their own PCs Users log in over the Internet Users’ experience is the same as if they were
sitting at the host computer’s local terminal
Remote user typically has to have a user ID and password
4. E-mail
The most commonly used feature of the Internet Network provides mail server :
Collects and stores messages in mailbox E-mail address consists of user name, followed by @
symbol, then domain name of mail server
E-mail client software on your computer Allows you to manage your e-mail messages Features Address books The ability to attach files Filters
Direct incoming e-mail to specific folders Block spam