computer application used to transfer files from one computer to another over a local area network (LAN) or a wide area network (WAN) such as the Internet.

First proposed by engineers in 1971 and developed for use on host computers at the Massachusetts Institute of Technology, FTP allows for reliable and swift exchange of information between computers with different operating systems (operating system) and machine architectures.

FTP advanced along with computer technology throughout the 1970s and '80s, becoming an international standard in 1985. In the 1990s the World Wide Web's hypertext transfer protocol (HTTP) began taking over as the chief means of exchanging smaller text and image files between computers over the Internet. However, FTP remained the primary way of transferring larger, more complex files such as database files, programs, music, and video. Many organizations also use FTP because it can be run automatically, requiring no user input. This is useful for transferring files at a regular time without having to wait for business hours. FTP is used extensively by Web designers and developers to upload Web pages and graphics onto Web servers, something a standard Web browser cannot do.

The open design of FTP, while revolutionary, poses a security risk that was not considered important in the 1970s when users were on LANs within one organization. FTP sends all information as plain text, which means that user names, user passwords, and commands sent over a network can be intercepted, read, and exploited by cybercriminals (cybercrime). Because of this, many security experts recommend switching to Secure FTP (SFTP) for transferring files.