FTP means File Transfer Protocol
With FTP, files can be transported from one computer to another. For example, FTP software sends Web sites to a server, and FTP is often used to send large files (which do not allow email due to size). FTP has been in existence since 1971 and has become the standard for sending files quite quickly. Like most Internet protocols, FTP is also based on client-server model: The client contacts a server (FTP uses TCP port 21 by default). After approval from both sides, the transfer of files can begin. Some FTP server allow anonymous access, but for most you need a user name and password.