what is microsoft office licensing?

I need to know a definition for ms office licensing. when and why do you need
it?

Its the Licence, or rights, that MS grants an end user to use their
copywrited software

"Kirsten Jurrens" <Kirsten Jurrens@discussions.microsoft.com> wrote in
message news:6B39DA8E-9623-4CE6-B8B6-6A3ED7FD96F4@microsoft.com...
>I need to know a definition for ms office licensing. when and why do you
>need
> it?