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A commonly asked question is, "What can I do on the Internet?". It's not easy to give a clear answer, because their a so many possibilities. You can send electronic messages, called e-mail, you can participate in discussion groups, called Newsgroups, you can download files and information from remote servers via FTP, you can access computers via Telnet, which gives you the opportunity to do research in databases, or you can simply surf around on the World Wide Web (WWW).
. Newsgroups: The Usenet, a collection of discussion groups called newsgroups, is one of the first and most used areas of the Internet. Usenet is a system similar to e-mail, but it is specifically designed to start ongoing discussions about interesting topics.
You can write an "article" addressed to the group, and it will be "posted" for everyone to read. People can then reply to your message either by sending you a private mail, or by posting a "response", which is also readable by everyone.
For participating in Newsgroups you need a client , program, which is called "Newsreader". This application receives a list of different newsgroups, which you are able to join.
Furthermore newsgroups are divided into the following hierarchies:
alt groups that discuss alternative subjects
comp Computer science and related topics
news Groups concerned with Usenet itself
rec Groups concerned with recreational activities (e.g. sports or arts)
sci Groups discussing scientific research
talk Debate on controversial issues, such as religion
misc Miscellaneous groups, that don't fall into other categories.
. e-mail: e-mail (electronic mail) is the exchange of computer-stored messages by telecommunication. Messages are usually encoded in ASCII text. However you can also send non-text files, such as graphic images and sound files as attachments in binary streams.
Another service, related with e-mails is mailing list, which is a list of people who subscribe to a periodic mailing distribution on a particular topic.
e-mail was one of the first uses of the Internet and is still the most popular use, because it delivers messages to the recipient within seconds under normal circumstances.
. IRC: Internet Relay Chat (IRC) is a system, that allows people from across the globe to exchange views and opinions, without having to leave their keyboards. The system is based on client/server software and a set of rules and conventions, called Netiquette .
With the chat client you can start a "chat group" (called channel) or join an existing one. In addition you have to choose a "nickname", that lasts only for the duration of the session (you can't "own" a nickname). Now you have the opportunity to chat with other people in public, or to invite them in a private virtual chat room.
IRC is especially used by young people, who seek contact over the Internet.
. FTP: FTP stands for File Transfer Protocol., which is the best method for moving large files, containing every king of data (e.g. documents, pictures, sounds or videos), across the Internet. As every Internet protocol FTP is a client/server protocol, that enables a FTP program (client) to log on to a remote machine, navigate the file system of that remote machine, and upload (send) and download (receive) files from that machine.
. Telnet: Telnet is a protocol, which allows a computer terminal to control a remote server. A local terminal program receives commands through the keyboard and sends them to the remote server. The commands are processed and the according information is sent back and displayed on your screen.
. Gopher: Gopher is an application protocol in which hierarchically-organized file structures are maintained on servers, which are part of an overall information structure. Gopher provided a way to bring text files from all over the world to a viewer on his/her computer. Popular for several years, especially in universities, Gopher was a step toward the World Wide Web's Hypertext Transfer Protocol. Many of the original file structures, especially those in universities, still exist and can be accessed through most Web browsers.
. WAIS: Wide-area information servers (WAIS) is an Internet system, in which specialized subject databases are created at multiple server locations. A "directory of servers" at one location is keeping track of all server locations. So it is made accessible for searching by users with WAIS client programs.
The user enters a search argument for a selected database. The client then accesses all the servers on which the database is distributed. The results provide a description of each text, that meets the search requirements. Finally the user can retrieve the full document (text).
Especially librarians, medical researchers, and others may find some specialized information available through WAIS that is not currently available on the Web (WWW).
. World Wide Web: When talking about the Internet most people refer to the World Wide Web (WWW, W3 or just "The Web"). Officially the World Wide Web is described as "wide-area hypermedia information retrieval initiative aiming to give universal access to a large universe of documents". Simplifying this description, the World Wide Web gives its' users a mean to access digital information of various kinds with computers over telephone lines. The different documents are stored on servers, which use many existing protocols to communicate with the client program. Despite of the different protocols additional ways of communication are required: HTTP, HTML and URL
. HTTP: The Hypertext Transfer Protocol (HTTP) is a set of commands for exchanging files (text, graphic images, sound, video, and other multimedia files) on the World Wide Web. Relative to the TCP/IP suite of protocols (which are the basis for information exchange on the Internet), HTTP is an application protocol.
. HTML: Hypertext Markup Language (HTML) is the standard language for creating files, which are intended to be viewed by Web browsers (e.g. Netscape Communicator and Microsoft Internet Explorer). The markup tells the Web browser how to arrange words and images on the screen for the user.
. URL: The Uniform Resource Locator (URL) provides the address of files, which are accessible on the Internet. With URLs many hypertext documents can be linked together.
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