PuTTY is a very useful tool, a small freeware implementation of Telnet and SSH for Win32 platforms, along with an xterm terminal emulator. SSH, Telnet and Rlogin are three ways of doing the same thing: logging in to a multi-user computer from another computer, over a network. PuTTY implements the client end of that session: the end at which the session is displayed, rather than the end at which it runs.
In really simple terms: you run PuTTY on a Windows machine, and tell it to connect to (for example) a Unix machine. PuTTY opens a window. Then, anything you type into that window is sent straight to the Unix machine, and everything the Unix machine sends back is displayed in the window. So you can work on the Unix machine as if you were sitting at its console, while actually sitting somewhere else.
- The storing of hosts and preferences for later use.
- Control over the SSH encryption key and protocol version.
- Command-line SCP and SFTP clients, called "pscp" and "psftp" respectively.
- Control over port forwarding with SSH (local, remote or dynamic port forwarding), including built-in handling of X11 forwarding.
- Emulates most xterm, VT102 control sequences, as well as much of ECMA-48 terminal emulation.
- IPv6 support.
- Supports 3DES, AES, Arcfour, Blowfish, DES.
- Public-key authentication support.
- Support for local serial port connections.
- Self-contained executable requires no installation.