The Internet and the World Wide Web

Network Connections

Server: A computer that accepts requests from other computers connected to it and shares some or all of its resources.

Client: Other computers connected to the server.

• The network operating system is the software that is run on the server.
• "Client/server networks commonly are used to connect device in a local area network (LAN): Devices are located in close proximity."

Ways to Connect: Wired v. Wireless

Wired: 

Twisted-pair cable is oldest type of cable comes with heavy electrical interference: A small flow of unwanted electricity in nearby objects, including other wires, created when a wire carries an electric current and generates an electromagnetic field around itself.

Category 1 cable: the type of twisted-pair cable that telephone companies have used for years to transmit voice signals. It is not a current cable standard.

Coaxial cable: 20 times faster than Category 1 cable, but much more expensive.

Category 5 cable: Carries signals between 10 and 100 times faster than coaxial cable and it's easy to install.

Category 5e cable, Cat6, and CAT 7: Is constructed of higher quality materials than the Category 5 cable.

Fiber-optic cable: Is most expensive type of cable; transmits pulsing beams of light through very thin strands of glass. It has the fastest transmission rate and doesn't use electricity.

Wireless:

• Is becoming more common as costs continue to drop. 
• Welcome in organizations that occupy old buildings. 
• Popular with companies whose employees use laptop computers. 
• Used by schools in classrooms, libraries, and study lounges. 
• Used in homes. 

Web Addresses

A Uniform Resource Locator (URL) is a four-part address that tells the Web browser:  

•  The transfer protocol to use when transporting the file.
• The domain name of the computer on which the file resides.
• The pathname of the folder or directory on which the file resides.
• The name of the file.

Inventing the Internet

1960s: ARPANET was created by  the Defense Advanced Research Projects Agency as a research  project for national defense. 

1969: DARPA researchers connected first computer switches. Grew to 20 in three years.

1970: Cerf and Kahn develop a new set of protocols. IP and TCP become standards.

1974: The term "Internet" is coined by Cerf and Kahn. 

Tutorial 1: Browser Basics

There are many different browsers available to internet users.

• Most browsers provide a walk-through and tutorials on there home websites. 
• Internet Explorer, Opera, Mozilla Firefox, and there are many more.
• Web browsers are used to navigate files available on Web servers.
• These files are also known as Web pages.
• Web pages are written in HTML (Hypertext Markup Language) and many Web pages are linked together using the HTML anchor tag, like those used above to link this page to the browser homepages. 

One of the many features of most Web browsers is a Favorites Center

 

• The Favorites Center, a.k.a Library is used to organize and save sites that interest you so you can easily return to them later.
• You can also access your history as well as feeds by using the Favorites Center. 

"All Web browser users should know about the use of cookies."

• "A cookie is a small text file that a Web server saves on the hard drive of the computer that is running the Web browser software."
• It is used to store information about your visit to a specific Web Site.
• There are first-party and third-party cookies.
• First-party cookie: "When the site you are visiting places a cookie on your computer."
• Third-party cookie: Cookies that are placed on your computer by a company other than the site you are visiting.

• More information about cookies can be found at: Cookie Central, How Cookies Work, and World Wide Web Security FAQ