In short, RAM is the "chalkboard" where your PC does all its work. The data on the chalkboard gets erased when you turn your PC off.

RAM comes in different types including DIPs, SIPPs, SIMMs, DIMMs, and EDO. Access time is measured in nanoseconds. Some RAM uses parity checking, while other RAM does not. Finally, the faster your RAM, the faster your CPU can process information.