Usually, I use the
scp command to transfer files on *nixes.
What's the difference between SFTP and SCP? Don't they both work on SSH?
In a nutshell, scp can only be used for transferring files, and it is non-interactive (i.e., everything has to be specified on the command line). sftp is more elaborate, and allows interactive commands to do things like creating directories, deleting directories and files (all subject to system permissions, of course), etc.
From a purely command line perspective :
Other important difference between the 2 commands is that sftp cannot put a local file to a remote location using a single command line, although it can get remote file, while scp can do both.
sftp get remote file
scp get remote file
scp put remote file