MS Office: How many computers??

Looking to buy the home version of MS Office.
Want install on both my iMac and MBP.

I'm little confused as to whether this is possible.
It says 1PC/1User.
Does that mean I can only use it on one machine?

From a quick search I've read you can install on one machine and others
say 2 machines.

For the one I want, is it 1 or 2 machines?

Thanks.

 

Thanks all for the responses!

Did not know about OpenOffice.
Like it even better that's free.

Could I also use google docs?
I have one excel file I need to work on my MPB.
Of course my MBP is the one that doesn't the software I need.