All About the Internet

All About The Internet

History of the Internet

What is the Internet?

The Internet is a giant, worldwide computer network. The transfer of data requires a server. Servers are connected by telephone lines.

Integrated Services Digital Network (ISDN) Digital Subscribers Line (DSL) Coaxial Fiber optic cable Satellite links

How Did the Internet Begin?

The 1950s-

The fear of a Nuclear war had people wondering how we would communicate in such an event. By 1969 the Advance Research Projects Agency brought the early Internet, then called ARPANET, on-line.

1960s & 1970s- The Internet matured. Library catalogs, newsgroups, and e-mail became the primary use of the then relativelyunknown network.1989- Tim Berners-Lee developed a programnamed the World Wide Web to be used as the protocol for distributing information overthe Internet.1992- The first commercial online service, Delphi, made the Internet accessible to subscribers.1993- The first browser, Mosaic, was released.

Protocols

Protocols are languages that computers use to communicate with each other. These computer languages consist of commands and written programming code that control the actions of the computer. Computers, however, face the same language problems that we humans do- not everyone speaks the same one.

Common Protocols TCP/IP- two separate protocols, Transmission

Control Protocol (TCP), and the Internet Protocol (IP).

HTTP- Hypertext Transfer Protocol (HTTP), the language Web browsers use to communicate with Web servers.

FTP- File Transfer Protocol (FTP) is used to send files from a Web server to a computer.

The World Wide Web

Web Browsers- displays a Web site’s information as text and pictures.

Hyperlinks- Links that allow the user to connect to another Web page. Links are usually underlined and a different color of text. Some links roll over or change when you run your mouse over them. A mouse pointer usually changes to a hand to indicate a link.

Getting Around the Internet

To go to a Web site, tell your browser the address of where you want to go. To do this type the Web address in the address bar of your browser. A Web address is also known as a URL-Uniform Resource Locator.

www.pepsi.com/sec/index/html

Location organization extension directory file file

name name type

Domain NamesName Extensions and Country Extensions

.com commercial

.net network .ca Canada

.edu educational .au Australia

.gov government .us United States

.mil military .uk United Kingdom

.org organization .jp Japan

Types of Files on the Internet

Pages- Most pages are written in HTML (Hypertext Markup Language) or XML (Extensible Markup Language)

Images- GIF, JPG, and PNG. Sound- WAV, MP3, and MP4. Video- AVI, MPG, MOV, and QT. Also Flash. Streaming Files- Large video or audio files are

often ‘streamed’ much like a radio or T.V. broadcast.

Compressed Files

Programs available that let you compress large files.

Common compressed file types Zip (Windows), HQX (Macintosh), and

SIT(Macintosh). Zip files are unzipped using a program

called WinZip, which is commonly found on many windows-based PCs.

Connecting to the Internet Dial-Up Connectivity- Modems transmit and

receive data at different speeds. The speeds are 28.8 or 56K. These numbers explain how many bits of data the modem can send or receive each second. Example a 56K modem can transmit 56,000 bits of data each second.

Drawbacks to a modem is it ties up the telephone line.

Connecting to the Internet Dedicated Connectivity- The computer or network

has a permanent connection to the Internet. This is accomplished with

ISDN Integrated Services Digital Network DSL Digital Subscribers Line T1 These are all high speed telecommunication lines

they move 100 times faster than a dial up link. They are more expensive than dial up.

Connecting to the Internet Another form of home connectivity is the

cable modem. This service uses coaxial cable wires to

transmit data and usually is bundled with home cable service. First, it frees up the phone line. Second, it is astronomically faster than using a modem.

E-mail It is faster than regular postal mail also

known as snail mail. Much cheaper than calling someone long-

distance. When you subscribe to an online service,

you will receive an e-mail address. They make their profit by showing banner

ads while you download your messages.

Chat Rooms They are like e-mail. These sites are on the Internet or are part

of an online service where users can gather in a virtual meeting room to discuss issues and ideas.

Comments are posted on the site instantaneously for everyone in the room to see.

Chat Rooms Sometimes it’s confusing when you first

enter a chat room because there are so many conversations going on at once.

Chat rooms are not always monitored. Almost anyone can enter a chat room on

the Internet. Sometimes anonymous users will show up

to cause problems.

Instant Messaging This technology was pioneered by AOL and is

available through Yahoo!, Microsoft Network, and others.

You can talk freely with others in a window that appears on your desktop.

You can invite more than one person to join in on the session, however only the people you invite will know there is an active session.

Instant Messaging To access this service you must first register a

screen name and a password with your ISP. While you are logged on, you will see a list of

other users’ screen names that you know and have previously entered into your buddy list.

Most of these services are paid for with banner ads.

Bulletin Boards and Newsgroups Public areas on the Internet, devoted to specific

subjects. Users can gather in an online community and

discuss common ideas and ask questions. For example, there are several sites on the Internet designed as question and answer sessions students can visit and ask a question like “How does photosynthesis work?” An expert in the BBS or newsgroup will respond with an answer.

Bulletin Boards and Newsgroups These services are safer than chat rooms

or e-mail because they are supervised and maintained by an administrator who can block users who cause problems.

Netiquette There’s a big difference between communicating

over the Internet and communicating with someone face-to-face, or even talking on the phone. When you talk with someone, you pick up nonverbal cues, such as body language, voice inflections, and facial expressions. When you communicate through e-mail, chat rooms, or within a BBS, none of this comes across.

Netiquette Rules The use of all caps indicates that YOU ARE

SHOUTING. It’s even acceptable to type everything in lowercase.

Proofread your messages. Use spell check.

Be polite Do not send rude or insulting messages.

Do not spam.

Netiquette Rules Avoid sending attachments unless you

know the recipient’s system can handle the message.

Do not swear. In fact, certain chat rooms, and BBS will restrict your access.

Keep your comments short.