If the question is understood correctly, there is some information on Apple's support site that should be handy, at least for PowerPC-based Macs and their respective shipping versions of Mac OS X. Please see link below.
The current version is Apple Mac OSX Lion
Apple's Macintosh computers use Apple's operating system known as OSX. The current version is OSX 10.8.#. Macintosh computers can also run the Windows and Linux operating systems, but those systems are not included in the purchase of the computer.
For computers the term OS refers to Operating System.
DOS, which stands for Disk Operating System.
The Apple Macintosh operating system is called Mac OS X.
All modern day computers have some form of operating system.
Apple's Macintosh computers use Apple's operating system known as OSX. The current version is OSX 10.8.#. Macintosh computers can also run the Windows and Linux operating systems, but those systems are not included in the purchase of the computer.
Yes, that is was the operating system of Macintosh Computers are called.
disk operating system
window operating system
OS not supported means that the software does not work with your current operating system. You may be able to update your operating system to the latest version or you may have to buy a new version of the operating system. If the latter you need to ensure that your computer is going to be able to handle the new operating system as older computers will have a slower processor, less memory etc. which may not suffice.
Yes, each version of "Windows" is an operating system.