There are different types of memory types in computer register, cache memory, magnetic tape, magnetic disk, RAM, ROM, But two of the major category are primary memory and secondary memory that we always talk about.
Primary memory is the essential first memory that will access the computer or CPU directly.
The primary memory stores the program to be executed holds the input data that is to be processed and the intermediate results of any calculation when the processing is being done.
We enter data -> program into computer -> first stored in the primary memory under the control of control unit.
All the data in primary memory will be stored on a temporary basis so that space doesn’t get blocked and processing goes better and faster.
Also, it’s called a volatile memory because A computer memory needs the power to maintain data; while powered on, the memory retains information, but when the power is interrupted, the memory loses it quickly.
- It is a semiconductor memory.
- In memory hierarchy, it is placed in the highest position due to high speed, high cost, and small size.
- Storing capacity is small.
- The processor directly accesses primary memory. Example RAM, ROM.
- Volatile memory (requires power to retain the data)
Secondary memory has larger space and size than the primary memory the are the permanent storage medium in the computer.
We can call secondary memory external memory where we store the data and the operating system for the computer.
Basically, as primary memory can’t have higher storage capacity so every work that happens in that computer will be stored in the secondary memory
A non-volatile memory device is a type of memory that can retain information even when the power is removed.
- It is magnetic and has optical memory.
- In memory hierarchy, it is placed in a lower position due to low speed, low and large size
- Its storing capacity is very large.
- The processor does not directly access secondary memory. It is accessed through the I/O interface or I/O processor.
- Example Floppy, ZIP-Floppy, Hard Disk, CD-ROM, VCD, WORM,
- None-volatile memory