PuTTY is a free and open-source terminal emulator, serial console and network file transfer application. It supports several network protocols, including SCP, SSH, Telnet, rlogin, and raw socket connection. It can also connect to a serial port. The name “PuTTY” has no official meaning.
WinSCP is a free and open-source SFTP client, FTP client, WebDAV client, Amazon S3 client, and SCP client for Microsoft Windows. Its main function is file transfer between a local and a remote computer. Beyond this, WinSCP offers scripting and basic file manager functionality.