10 June 2020

Difference Between RAM and ROM

RAM and ROM both are computer memory. RAM is used to store computer programs and data that CPU needs in real-time, ROM have preprocessed data and it is used to boot the computer. RAM data is static and remains in the computer even if computer switched off.

What is RAM?


RAM stands for random access memory. It allows read and writes the operation of data by the users. It is referred to as transferred memory because the data present in this memory last only till the time the power supply is ON.

What is ROM?


ROM stands for read-only memory.  ROM is the name itself is indicating that only read operation can be performed on this memory. This mean the data in ROM is stored at the time of designing the system and hence user does not hold the authority to change the data present in it.

The main key difference between RAM and ROM are listed below:


  • RAM stands for random access memory, While the ROM stand for read-only memory.
  • In RAM data is volatile. Data is present till power supply is present while the ROM data is permanent. Data remains even after power supply is not present.
  • CPU can access data stored on RAM, While the Data to be copied from ROM to RAM so that CPU can access its data.
  • RAM speed is quite high, ROM speed is slover than RAM.
  • RAM offers the user to read as well the write the data but the data in ROM is pre-written and thus can only be read by users, So RAM data can be read, erased, or modified while ROM data is read-only.
  • RAM is a temporary storage type of memory as the day lasts only till the time the power supply is ON. While in ROM is a permanent memory that retains the data for a longer duration.
  • RAM is costly while the ROM is cheap.
  • RAM is classified as the main primary memory of the system whereas the ROM categorized as the secondary memory.
  • RAM is used as CPU cache, primary memory of the system while the ROM is used as firmware by the microcontroller.
  • The process can directly access the data present in RAM, while the data present in ROM do not permit direct access to the processor.
  • The data stored in RAM is changeable by the user, Whereas the data in ROM cannot be altered by the user.
  • RAM memory is a large and high capacity, While is ROM is generally small and low capacity.
  • RAM is used to store data that CPU need for current instruction processing, ROM is used to store data needed to bootstrap the computer.
  • RAM stores data on transistor thus requires a continuous source of power while the data stored in ROM remain unaffected with power failure.
  • RAM offers memory capacity in GB usually 1 to 256 GB per ship, While the ROM permits the storage capacity in MB, usually in the range 4 to 8 MB per chip.