RAM (Random Access Memory) and ROM (Read Only memory) both are a Primary memory of a computer system. Although they both are the memory they are different from one another in different ways like price, function, size, Speed etc. Before getting into the difference between RAM and ROM let’s first find out what they really are.

RAM

RAM is a primary memory that stores the programs or files currently being executed by the CPU. CPU can read data from and write data to the RAM memory so it is also called read and write memory. All the files and programs are permanently stored in Secondary storage devices like Hard disk, CD-DVD, Floppy disk etc. Since CPU cannot directly access the resources stored in the Secondary storage, the program is brought to RAM for processing. This process is called program “loading”. When you run Word processing software to write a letter or an essay, or VLC media player to watch a movie, the programs like VLC and MS word Operating System loads those program into the RAM and then CPU executes it.

RAM is a volatile memory or a temporary memory. The program data loaded on this memory remains as long as the computer is on. Once the computer is turned off all the program and files get erased. When the program loaded in RAM is closed the program is erased but the program data might still be there so that the CPU doesn’t have to re-read required data from the hard disk. It stores frequently used data. The operating system of Computer is responsible for loading and erasing the program. The RAM memory is generally faster than the hard disk or any other secondary storage device.

Types of RAM:

SRAM

It stands for Static random access memory. It is faster and more expensive than DRAM.

This is SRAM

DRAM

DRAM stands for dynamic random access memory. It is cheaper than SRAM. Most of the computer uses this type of RAM.

Picture of DRAM

Read Only Memory(ROM)

ROM

ROM stands for Read only memory. ROM is read only memory. CPU can read the instruction from this memory but it can’t write data into ROM. ROM stores different critical instructions that are required to boot up the computer, like BIOS(Basic Input Output System). ROM is a non-volatile memory. The instruction of ROM doesn’t get erased even if the computer is turned off. ROM are used on computers as well as other basic electronic devices like a washing machine, some digital watches, robots etc.

Difference between RAM and ROM.

Key Difference between RAM and ROM

RAM	ROM
It stands for Random access memory.	ROM stands for Read Only memory.
It is volatile memory	It is not volatile memory
Reading data from and writing data to RAM is much faster.	Reading data from ROM is comparatively slower process
RAM chip can store a huge large amount of data ( 16 GB or more) than ROM	It can store very less amount of data. A sing ROM chip can store up to 4 MB or little more.
Static RAM and Dynamic RAM are common two types of RAM.	PROM, EPROM, EEPROM etc are types of ROM.
RAM plays role in speed of a computer. Generally, more ram means computer works faster. So adding up another RAM stick can improve the performance of a computer.	ROM doesn’t play any role in speeding up the computer.
RAM is expensive.	It is cheaper than RAM.
RAM stores the programs that CPU is currently executing.	It stores boot information like ROM.
It is Read and Write memory. CPU can read the data from and also write the data/information to RAM.	It is a Read-only memory. A Computer can only read the instruction stored in this memory.