The Internet, commonly called "The Net," was originally designed by the U.S. Department of Defense in 1969 as an experimental project called ARPANET. It was intended to link researchers to information sources. Today the Internet links tens of millions of networks, and tens of millions of people use it to communicate and get information.
The Internet is not one network but many networks linked together, including Local Area Networks (LANs), Metropolitan Area Networks (MANs) and Wide Area Networks (WANs). All these networks span the whole globe, connecting computers worldwide. There are established standards of operation that all the participants are supposed to follow, making access to the Net uniform and predictable.
You are most likely to communicate with the Internet via the World Wide Web, its graphical interface component. By pointing and clicking with your mouse, you can get information of almost any kind delivered to your computer screen, from scientific research papers to local movie schedules, in most cases for free.
The terms "Web" and "Internet" have
become practically interchangeable in common usage.
There are two ways to connect to the Internet:
Dedicated connections are maintained through a network belonging to an organization connected to the rest of Net via a high-speed digital connection.
Dial-Up connections are how
most individual users gain access to the Net. Your computer uses a modem
to dial up a service provider that connects you to its computers
and from there to the Internet.
Internet Service Provider (ISP):
AOL, Prodigy, and Microsoft Network
are a few of the many service providers. Regional telephone companies and
television cable companies have also begun to offer Internet services.
Usually for a set monthly fee the service provider connects you to the
Internet via a toll-free telephone number. The service provider also supplies
you with its own proprietary software that, together with your browser,
takes care of the technical aspects of Internet communication. Most major
commercial ISPs give away software disks together with a free trial period,
so that you can sample the ISP before you sign up. The disks are sometimes
included with other computer software packages, tucked into Internet magazines,
and sent out by direct mail. You can also call the ISP and ask if they
have a free offer, and if theyíll send you a disk.
There are also local and specialty service providers (like Juno, which offers only free E-mail).
Browsers are software for your computer that manage your connection to your service provider. The two most common are Microsoftís Internet Explorer and Netscape Navigator. A good browser has the capability to guide you through the steps of most Internet processes, including E-mail and FTP. Most computers that come with bundled software include a browser. They are also available at software stores.
Computers communicate by their own
languages and protocols. The communications protocol for the Internet is
TCP/IP, which stands for Transmission Control Protocol/Internet
Protocol. Internet computers assemble data, whether pictures or text, into
packets. Each packet contains an address. Computers examine each packet
as it arrives and bounce it on to a connected computer until the packet
reaches its destination. This process is called packet switching. Most
Internet documents are written in Hypertext Markup Language (HTML).
But you will probably never be aware that you are working with TCP/IP and
HTML because your browser and Internet service provider are
designed to manage the technical processes for you.
The three most common applications of the Internet are electronic mail (E-mail), File Transfer and Remote Login.
E-mail allows you to send messages to other computer users, including plain letters but also attached pictures, spreadsheets, and even computer programs. When you send an E-mail message via computer to your correspondent, it arrives in another computer and stays there until your correspondent retrieves it. You can send E-mail to everyone with an E-mail address, whether or not theyíre on the same ISP as you. In theory E-mail messages travel at the speed of light. So they do, but they travel by bouncing from computer to computer until they reach their destinations. If the relaying computers are busy, they canít resend your message instantly. Most E-mail messages arrive in seconds, but a delay of several minutes is not uncommon, and in rare circumstances a delay of one or more days is possible.
A simple E-mail message canít contain a virus Ė at least, not so far. But almost any attachment can. Be wary of E-mail with attachments if you donít know the source. There are many commercial virus protection programs available, Norton, McAfee, Dr. Solomon and Innoculan, to name a few. Computer magazines frequently print reviews of the available programs.
File transfers between computers can be managed under a file transfer protocol or FTP, and your browser probably has a module to help you manage the process.
Remote login, also known as Telnet,
enables you to use applications and programs that are running on another
computer. It allows you access to a host of databases and services from
library catalogs to bulletin boards.
Sifting Through the Information
There are thousands of information sources, known as sites, connected to the Internet. Each site may have several areas of information called Web pages. How do you get the information you want?
Universal Resource Locator (URL)
Each Web page has its own specific address or URL. Entering the URL for a page in the Location text box of your browser will take you directly to that page. For example, you can get to CT Advantage by entering http://www.ctadvantage.com.
If you donít know where to find information, or donít know the exact URL of a page you want to visit, you can use a search engine. Your browser and ISP probably give you the option to choose among several, such as Excite, Infoseek, Lycos, WebCrawler, and Yahoo! Enter the subject about which you want information and the search engine will return a list of pages related to the topic. The more specific you make your search request the better, because a search can easily return hundreds of pages. Your ISP may have a module that helps you refine the search.
See also: Navigation Hints