PC predominately stands for "Personal Computer" to the crowd reading this node. It started out innocently enough as an abbreviation for computers that IBM started making for personal use.

IBM was a mainframe and business computing company. They really were going out on a limb when they decided to start selling computers to the public. Much like the internet, they saw a trend in the hobby computer market, and that many businesses were becoming well known and successful by selling computers to individual users rather than large corporations.

They marketted the IBM personal computer, or IBM PC, and were fairly succesful. Luckily (as I don't think it was thought out in the long run) they didn't aggresively pursue companies duplicating their efforts, after all, they were IBM (insert ominous music here, huge dark building with a backdrop of dark, lightning lit skies), really, who could compete with their reputation?

Apple chose not to refer to their computers as PCs since the abbreviation was so ingrained in people's minds as "IBM", and even now there is a sharp differentiation. Technically correct(TC) people will refer to x86 based systems as "IBM compatibles" (the programs that ran on the first IBM PC still run on today's systems), or, even better, x86 based systems. x86 is depreciated now since Intel could not trademark a number (80486, 80586, 80686) and instead named their next series of processor as the "pentium". (refusing to go to sextium - the propor name forthe next generation, they've added a number after the name pentium. If you were to number the current processors, it would probably be 80486, 80586, 80586 pro, 805286, 805386, 805486, with various xoen (DX) and celeron (SX) extras thrown in for good measure).

At any rate. Many lay people do not connote PC with IBM or x86 compatibles, as apple and other companies are still calling their computers "Personal Computer", though stressing other tradmarked names such as iMac, etc.

If IBM had trademarked "PC" and "Personal Computer", or taken patents out on the design of their computer (there are portions which could have been patented, though the basic x86 design was pretty much taken straight from Intel's design guides) then the computing landscape would be so different today as to be nearly incomprehendable to us.