Types of Computer Memory

Types of Computer Memory

Three main types of physical memory are used in modern PCs:

1. ROM: Read-only memory 
2. DRAM: Dynamic random access memory 
3. SRAM: Static RAM 

The speed of memory used to be expressed in ns (nanoseconds), and that of processor in MHz (megahertz). Newer and faster types of memory have speeds expressed in MHz A nanosecond is defined as one billionth of a second.