The CPU Box is the part that, well, looks like a box. CPU Box is not really a good name for it, but it will have to do until somebody comes up with a name everybody can agree on. CPU stands for Central Processing Unit, and technical people refer to the box part as the CPU Box because that's where the CPU is, and that's where the real work gets done. Because that's where the computing is really done, the CPU component alone can be called the computer. You might hear people say, "not the screen, but the actual computer" when referring to the CPU box. Some people refer to it as the hard drive, since the hard drive is in there too, but that is confusing. The hard drive is inside the CPU Box all right, but you'll drive technical people bonkers if you call the box a hard drive, because they just don't think that way. Of course it's not logical to say that CPU is an OK name but hard drive isn't, but remember that technical people aren't normal and humor them. A box is a box, but not if it's a CPU Box. CPU Boxes come in two special types, called Desktop and Tower. The Desktop kind is designed to lie down flat, even though you can stand it on its side if you want to. In a desktop CPU Box, you will normally find that the openings for the CD and Floppy disk drives are horizontal when the CPU Box is lying down flat. A lot of people don't keep their CPU Box lying flat on top of their desk any more, but the name has persisted. A Tower CPU Box is designed to stand up tall, so it will be easier to knock it over. Well, no, it's really supposed to stand under your desk and not take up too much floor space. In a Tower CPU Box, you will usually find that the openings for the CD and Floppy disk drives are horizontal when the CPU Box is standing up on what you might think was its side. Another clue is the writing on the box. Usually, the computer manufacturer will put the brand name and maybe the model number somewhere on the outside, usually on the part they think of as the front, and the words will be right side up when the CPU Box is standing or lying the way they had in mind when they designed it. This seems pretty complicated, and you're probably wondering why anybody cares. Unfortunately, sometimes it does matter. The parts inside the CPU Box are often different, depending on whether it was designed as a Desktop or a Tower. If you can identify which kind it is when you need help, a technical person may be able to resolve your problem more easily.