FTP is the simplest file transfer protocol to exchange files to and from a remote computer or network system. Similar to Windows, Linux, and UNIX operating systems they also have built-in command-line prompts that can be used as FTP clients to establish FTP connection. FTP works in Client-Server architecture to communicate and transfer the file during an established FTP session.  When the Client initiates a connection to the server, it’s called Passive Connection. Whereas when Server initiates a connection to the client, it’s called Active Connection. In Phase 1, When Connection initiated with the server, User credentials are passed for authentication. This is the control connection phase. In Phase 2, When actual data is transferred between client & server, This is data connection phase.