1) The processor (CPU). This is the 'brain' of the computer and is the chip where all the computing is done. The processor is usually inserted into a socket and therefore removable, but occasionally is soldered directly to the motherboard (as in the case of the Intel Atom). The processor is usually completely obscured from view by a large heat sink, to help remove heat and prevent it from burning out.

2) The memory. This is where the computer stores information while it is working on it. Computer memory these days is typically installed on long, narrow boards called SIMMs, or "Single Inline Memory Modules" into matching sockets. SIMMs come in varying sizes, including 2Gig, 4Gig, 8Gig, etc. There may be one or many of these installed on a board. The maximum amount of memory allowed on a board depends on a number of factors, including the processor, BIOS, and the board itself. The memory is almost always easily removable.

3) The "Chipset". This is a loosely coined term that may refer to one chip or a whole set of them. The Chipset is a link between the processor and the outside world, and handles things like controlling the hard drives, the USB ports, the keyboard and mouse, generates the sounds the computer makes, and sometimes even creates the pictures you see on the screen. The chipset may also have heatsink(s) attached to them. The chipset is almost always soldered directly to the motherboard.

4) The "Expansion Slots". These are connectors that allow you to attach additional "cards" on the computer, such as video cards, sound cards, modems, and add abilities to your computer that the motherboard doesn't provide. Some types of slots in use today called "PCI" or "PCI-E" slots. Older style slots include "AGP" and "ISA". In past years, many of these slots were needed to create a fully operational computer. As time goes on, more and more functions are being