PuTTY is a free and open-source terminal emulator, serial console, and network file transfer application. It was originally written for Microsoft Windows, but it has been ported to various other operating systems. PuTTY supports several network protocols, including SCP, SSH, Telnet, rlogin, and raw socket connection. It can also connect to a serial port. PuTTY is most commonly used as a File Transfer Protocol, and it can connect to a remote machine through SSH. SSH (Secure shell) is a protocol that allows a secure connection, and in this way, a PC can securely send and receive data from a remote server. PuTTY provides various file transfer features like FTP and SFTP, depending on the users security requirements. PuTTY is the worlds most popular free SSH and telnet client. It supports SSH, telnet, and raw socket connections with several features. PuTTY is a versatile terminal program for Windows. It is the worlds most popular free SSH client. PuTTY also supports connecting to serial ports and raw sockets, which can sometimes be useful for debugging purposes and for working with some legacy devices. PuTTY is written in C language and is monolithic, meaning it does not use dynamic link libraries. It is ready to be executed once the appropriate version is downloaded.