File Transfer Protocol, commonly referred to as FTP, was one of the original tools built by the architects of the Internet so that research results could be shared more easily. FTP allows the transfer of a copy of a computer file from a user's account on one computer to a user's account on a different computer located across the room or across the world. The file may contain text, graphics, audio, or video. It may be small or extremely large. It may be a file which two users have agreed to share, as in the case of scientists from different part of the country collaborating on a research project. Or it may be a file which has been posted for anyone and everyone to access and copy if they wish.
The latter example is usually referred to as "anonymous FTP". This name derives from the fact that space has been set aside on a given computer to make files freely available to any users on the network who log-on to the computer with the userid "anonymous". When using this account, the password is commonly the word "guest", or your email address. The computer will prompt you for what it needs.
There are thousands of "anonymous FTP sites" around the world which are computers owned and maintained by universities, corporations, non-profit organizations, and individuals. The files contain "free-ware" and "share-ware" computer programs, text files on hundreds of topics, and data collected by governement agencies, etc. These computer sites and the network access to these sites is provided free of charge, therefore certain courtesies are expected when using anonymous FTP sites. These include providing your email address when requested (this is often used to track usage and traffic patterns) and transferring large files only during non-peak hours.