File Transfer Protocol (FTP) is used to transfer files from a computer/client/server on a network and access online archives. Its architecture is built on a client-server model and uses TCP to guarantee delivery of files. By authenticating themselves with clear-text sign-in protocols (username/passwords), users can enjoy the secure transmission of encrypted data. This protection offered is often secured with SSL/TLS or SFTP. To determine how the connection is established, FTP can run in passive or active mode.
Active mode allows the client to listen for incoming data connections, where passive has the client behind a firewall which prevents incoming TCP connections. FTP is accessed through the command prompt. A typical FTP client, FileZilla, enables a user to browse available folders on a specific computer. Another way to accomplish the file transfer capabilities of FTP is by using Trivial File Transfer Protocol (TFTP). TFTP is a smaller version of FTP which allows reduced traffic. Hypertext Transfer Protocol (HTTP) also allows for file transfers, but FTP is much more robust. FTP is useful in corporate settings and is often used to manage web-page servers.
Gibson, Darril. (2011). Sybex. Microsoft Windows Networking Essentials. Exam 98-366.