Memory

We learned that the CPU is where computations and decisions are made, and that it is the heart of a computer. What is the purpose, then, of having main memory installed in the computer?

Main memory, which is also commonly called RAM (= Random Access Memory, due to it working like an array that you can access at any spot,) primary memory, or read-write memory, is used to store data, temporary configurations, and other information that the computer needs while running.

• Since the CPU has a small storage space, RAM also stores the instructions (code) of the currently running programs.

Before the computer shuts down, all the important data that is stored in main memory is saved to disk (for future access by the user or the operating system.) The rest is erased.

Main memory is organized as a linear (simple, one-dimensional) array of words, each of which is several bytes long.