Every location or cell has a unique address which differs from zero to memory size minus one. Read More : Basic Computer Knowledge Memory is of three types Cache Memory Primary Memory Secondary Memory Cache Memory Cache memory is a very high-speed semiconductor memory that can speed up CPU. It has limited capacity and data is vanished when power is switched off. RAM : The RAM is the place in a computer where the operating system, application programs, and data in current use are kept. RAM is much quick to read from and write to than the other types of storage in a computer, the hard disk, floppy disk, and CD-ROM. It has two parts: SRAM: Static Random Access Memory DRAM: Dynamic Random Access Memory.