PuTTY is a free implementation of Telnet and SSH for Windows and Unix platforms, along with an xterm terminal emulator. It is written and maintained primarily by Simon Tatham.

FileZilla Client is a fast and reliable cross-platform FTP, FTPS and SFTP client with lots of useful features and an intuitive graphical user interface.
Features

Among others, the features of FileZilla include the following:
Easy to use
Supports FTP, FTP over SSL/TLS (FTPS) and SSH File Transfer Protocol (SFTP)
Cross-platform. Runs on Windows, Linux, *BSD, Mac OS X and more
IPv6 support
Available in many languages
Supports resume and transfer of large files >4GB
Tabbed user interface
Powerful Site Manager and transfer queue
Bookmarks
Drag & drop support
Configurable transfer speed limits
Filename filters
Directory comparison