Difference Between RAM and ROM Memory

RAM and ROM both are the internal memories of the computer. Where RAM is a temporary memory, ROM is a permanent memory of the computer. There are many differences between RAM and ROM, but the basic difference is that RAM is a read-write memory and the ROM is a read only memory.

I have discussed some differences between RAM and ROM with the help of comparison chart shown below.

Content: RAM Vs ROM

1. Comparison Chart
2. Definition
3. Key Differences
4. Conclusion

Comparison Chart

Basis for Comparison	RAM	ROM
Basic	It is a read-write memory.	It is read only memory.
Use	Used to store the data that has to be currently processed by CPU temporarily.	It stores the instructions required during bootstrap of the computer.
Volatility	It is a volatile memory.	It is a nonvolatile memory.
Stands for	Random Access Memory.	Read Only Memory.
Modification	Data in RAM can be modified.	Data in ROM can not be modified.
Capacity	RAM sizes from 64 MB to 4GB.	ROM is comparatively smaller than RAM.
Cost	RAM is a costlier memory.	ROM is comparatively cheaper than RAM.
Type	Types of RAM are static RAM and dynamic RAM.	Types of ROM are PROM, EPROM, EEPROM.

Definition of RAM

RAM is a Random access memory; it means the CPU can directly access any address location of RAM memory.  RAM is a quickly accessible memory of the computer. It stores the data temporarily.

RAM is a volatile memory. RAM stores the data till the power is switched on. Once the power of the CPU is switched off the whole data in RAM gets erased. The data which has to be currently processed must be in RAM.  The storage capacity of the RAM ranges from 64 MB to 4 GB.

RAM is the fastest and costliest memory of the computer. It is a read-write memory of the computer. The processor can read the instructions from RAM and write the result to the RAM. The data in RAM can be modified.

There are two kinds of RAM, Static RAM and Dynamic RAM.

• Static RAM is one which requires the constant flow of the power to retain the data inside it. It is faster and more expensive than DRAM. It is used as a cache memory for the computer.
• Dynamic RAM needs to be refreshed to retain the data it holds. It is slower and cheaper than static RAM.

Definition of ROM

ROM is a Read Only Memory.  The data in ROM can only be read by CPU but, it can not be modified. The CPU can not directly access the ROM memory, the data has to be first transferred to the RAM, and then the CPU can access that data from the RAM.

ROM stores the instruction that computer requires during Bootstraping (a process of booting up of the computer). The content in ROM can not be modified. ROM is a non-volatile memory, the data inside the ROM retains even if the power of the CPU is switched off.

The capacity of ROM is comparatively smaller than RAM, it slower and cheaper than RAM. There many kinds of ROM that are as follow:

• PROM: Programmable ROM, it can be modified only once by the user.
• EPROM: Erasable and Programmable ROM, the content of this ROM can be erased using ultraviolet rays and the ROm can be reprogrammed.
• EEPROM: Electrically Erasable and Programmable ROM, it can be erased electrically and reprogrammed about ten thousand times.

Conclusion

RAM and ROM both are the necessary memory for the computer. ROM is a necessary for a computer to boot up. RAM is important for CPU processing.