After yesterdays feature rich tool, today an easy one..
You might know the standard syntax.
~$ mv source destination
But there are some more tricks mv can do..

I'll start with the most common options
If you don't want to be prompted before overwriting use the -f or --force option.
If you do want to be prompted you can use the -i op --interactive option.
These settings can also be toggled with the more obscure --reply= option. This one needs either yes, no or query as a vallue.. The yes is the same as force, the query equals interactive mode and the no vallue will make mv not overwrite any existing files..

The -b or --backup option is for making backups of files before overwriting.
The standard backup form is filename~, but it can be set to something else with the --suffix option.

Instead of making backups or overwriting all files there is also an update feature.
The -u option or --update will only overwrite a file if the source file is newer then the destination, or the destination file is missing..

This information was based on mv from coreutils 5.2.1