Installing another operating system

[Cheetah Designs]

I have an old iMac

If I wipe the drive and install another operating system (lets say Ubuntu)....would I be able to restory back to OSX at a later point using the CMD + R boot menu? (I.e. is that boot menu separate from the drive that I will wipe...or do I need to be careful not to wipe a certain partition?)

 

[Cheetah Designs]

Its a last 2012 iMac with Mountian Lion on. I think I've figured it out. From Disk Utility there is a separate disk in there called "disk2" which ahs the "Mac OSX X Base System" on it. If I'm reading Google correctly - this is the recovery tool that will allow me to download Mountain Lion from the internet.