What is the Internet?

Thousands of networks connected Purpose of exchanging information World wide

No one owns the Internet It started because of Sputnik

Internet is hardware

Physical connections Towers, wires, hubs, servers, etc.

Now maintained by major Internet Service Providers MCI Worldcom, Sprint, GTE, ANS, and UUNET

Types of connections Analog (dial up) DSL (always on) Cable Wireless (radio frequency) T1, T2 lines (leased) Satellite

How did the Internet get started? 1950’s US and Russia in Cold War US tried to get advantage Advanced Research Projects Agency

(ARPA) in 1958 Connected four computers Grew from that point on

http://www.youtube.com/watch?v=gNeIlc5HCdM&feature=related

World Wide Web is software (programs)

Collection of electronic documents Linked together like spider web Stored in many locations

Uses servers all over the globe Accessing documents through

Internet connections

What is the Web?

What makes up the Web?

Personal computer or handheld device Web browser software Internet service provider (ISP) Servers Routers and switches

How the Web works

Web pages Stored on web servers  Copied and sent to your

device URL (Uniform Resource

Locator) Web browser

Web Browsers Software program used to access

World Wide Web Retrieves data from remote web server Displays web page Popular browsers –

Microsoft-Internet Explorer Mozilla-Firefox Google-Chrome Apple-Safari Opera (from Norway)

Most browsers work the same way

Using Web URLs

Uniform Resource Locator Unique address Identifies web page location on server

URL MUST be typed exactly Some large websites have multiple URLs Address bar on your browser

 

Anatomy of a URL

o http:// -- Hypertext Transfer Protocolo Set of rules for transferring fileso Needs host (server) and client (your device)

o www. -- indicates the page is available on the World Wide Web

o learnthenet.com/ -- Domain nameo Main part of the URLo Indicates the web server name

o english/ -- directory or folder on the web servero start.htm -- a web page inside the english folder

Web pages o Single electronic documento Written in computer language

o HTML (Hypertext Markup Language)

o URL (Uniform Resource Locator)o Hyperlinks to other web pages

Websites

o One or more web pageso Linked togethero Relate to a common theme

o Home pageo First page of the siteo “Front door” 

o Hyperlinkso Used to access other web pageso Internal or external

Navigating the Web o Three main ways to move between

web pages or websiteso Type URL in address baro Click a text hyperlinko Clicking a hyperlinked graphic image

o Buttono Photographo Drawing

Identifying hyperlinks o Text or graphic that references URL’s of other

web pageso Hypertext link

o Underlinedo Different color (usually blue)

o Turns purple after being usedo Graphic

o Move pointer over the imageo If pointer turns into a hando If URL appears in the status bar at the lower left of your web

browser.

How hyperlinks worko Text or graphic hyperlink hides a

URLo Clicking hyperlink passes URL to

browsero Follows image map

o Takes you to different web pageo Or different place on the same page

o Similar to a real-life bookmarko Acts as marker for a Web site o “Holds your place”o Faster way to get to page

o Add the bookmark to your favoriteso Navigate to web page o Choose "Add to Favorites”o Favorites list or Favorites Bar

Bookmark

Printing a Web Page

o Print button on toolbar will print entire web pageo Could be several (or several

hundred) pages longo Always use File menu and Print

commando Can select what you want to printo Can also Print Preview to see how

much will print

Other printing optionso Highlight the content you

want to printo File menu and Print

commando Click on Selectiono Prints just what you have

selected instead of the whole page

o Or copy selected text o Paste in a Word documento Print this document