but mac and PC are so much different. so its like saying apple vs orange. and linux is pear. always pear.
Mac (Macintosh series of personal computers) - Personal computer made by Apple
PC - Personal computer - a generic name for the device
MAC OS X- The operating system on a Mac PC.
Windows - An operating system from Microsoft
Linux - An operating system that is open source. It has different flavors.
An operating system is a software. A PC is a piece of hardware. Hope that is clear ^^