SFTP, or Secure FTP, uses SSH to encrypt and then securely transmit data across a potentially insecure connection. Functionally SFTP is similar to FTP, but offers protection to sensitive data. At Joyent you will only be able to access your account with SFTP rather than FTP for security reasons.
There are many free and commercial FTP applications that support SFTP. For Windows there is Filezilla (free) and WinSCP (free); for the Mac there is Fugu (free) and Transmit (Commercial). And for both platforms, the latest version of Dreamweaver supports SFTP as well. Linux and UNIX based systems typically come with a command line sftp tool, too.
Setting up SFTP is pretty much the same for most of the above FTP applications, but we’ll show you how to setup a few of the common ones. If you’ve created another user for your account, all the following will apply except any instance of a username or password will be the user name and password of your user.