Internet (2)

E-mail, mailing lists, file transfer and other. Email is the most basic Internet application, and probably the one that is most often used. Today, email client software supports formatting and MIME (Multipurpose Internet Mail Extension) allows for attaching files containing documents, spreadsheets, power point presentations, electronic pictures, sounds and movies - whatever can be put in file form. Email messages are passed through the Internet using a protocol Simple Mail Transfer Protocol (SMTP). Since email can arrive at any time, one needs an email mailbox that resides on a mail server which is permanently attached to the Internet. Mail servers receive and store email messages using a protocol called Post Office Protocol (POP) - 'cyber-technicians' call them therefore servers. Most people do not have a computer that is permanently attached to the Internet - instead, they dial in and connect to the mail server of an Internet Service Provider (ISP), which keeps their email mailbox.

Besides email, there are other Internet applications, such as 'mailing lists', 'newsgroups', 'file transfer the 'World Wide Web' (other applications such as 'telnet', 'gopher', 'online chat' and 'voice and conferencing' are not discussed here).

Mailing lists enables groups of Internet users to communicate using email. The mailing list software сan be configured in various ways, allowing everyone to subscribe or requiring approval of subscribes (closed lists). Mailing lists can be configured so that only a restricted number of persons can post messages to the list that is circulated among all subscribers. It can also be arranged that person receives all messages, and reviews and approves or rejects them, before posting them to the list. Mailing lists are used by groups of people with a common interest, such as researches collaborating in a project, or people who are interested in a specific subject.

Newsgroups are the oldest Internet application for global distribution of information - a decade older the World Wide Web. Usenet, a public system of hundreds of news servers and thousands of newsgroup enables people to exchange messages on a huge variety of subjects. The system is like a worldwide box, with each newsgroup concentrating on one topic. Once posted in a newsgroup on a news server, a message is copied from one news server to another until all servers carrying that particular newsgroup received it. As with mailing lists, users can read and respond to articles at any time, according to their schedule. Unlike mailing lists, anyone can read the articles, without subscribing a particular newsgroup.

File transfer also is an 'old' Internet application that is frequently used to distribute files, using a 'file transfer protocol' (FTP) and a client-server system that stores files at a central server-computer and distributes files between that computer and other, widely distributed client-computers. Using FTP, the client requests that a file transfer be initiated, after which the server and the client exchange data. FTP has almost faded into oblivion since the World Wide Web took over many of its functions.