It works in tandem with the Central Processing Unit, or microprocessor, to store data, programs, and processed information that can be made immediately and directly accessible to the CPU or to other system devices. Memory is central to a computer's operation because it forms the size and number of programs that can be run simultaneously, and helps to optimize the capabilities of increasingly powerful microprocessors. There are many different kinds of memory, each with its own features and benefits. Unfortunately, with so many different types of memory types of memory, it can be easy to get them confused. Mass storage includes hard drives, floppy diskettes, magnetic tapes, and cd discs.
Computer memory is temporary.
The most common analogy is the desk. The top of the desk is your work area. That is the area for the memory. When you have finished working then you store your files in the desk drawer, the hard drive. These memory modules require 'refreshing' - or else they forget.