Difference Between RAM and ROM
RAM, otherwise called as Random Access Memory maintains the data only when the system has in use. It stores the information in temporary forms and requires power to store data. The size is more and also it is costly when compared with ROM. We can use RAM for both read and write operations. ROM (Read Only Memory) stores the content even if the system is not in use so that the information is stored permanently. It can be used only for read operations and the cost is very less. The size is small and the capacity is also less. RAM is used in CPU cache whereas ROM is used in microcontrollers.
- Every computer has some form of storage, which stores data and machine code currently under execution. A RAM i.e. random-access memory device provides the same purpose, which allows read and write of data in the same amount of time. RAM devices have many data lines to address this storage requirement. Modern world RAM devices are known to have volatile types of memory, the information would be lost if power is removed, even though non-volatile RAM is also being developed. RAM is also available in the form of integrated circuits. There are other non-volatile memories as well in the market, which have certain restrictions like they allow random access for a read type operation but won’t allow write operations.
- There are two types of RAM which are widely available in the modern computer world, SRAM i.e. static RAM and DRAM i.e. dynamic RAM. SRAM is expensive to produce, which stores every bit of data using the state of a transistor memory cell. SRAM is faster and needs less power than DRAM, thus utilized by the modern computer chiefly as cache memory. DRAM, on the other hand, store a bit of data using a pair having a transistor and capacitor. Since it is cheaper to produce as compared to SRAM, they are widely used in computers across the world. Both SRAM and DRAM are volatile in nature since they lost their state when power is switched off for the system. More specifically, they are responsible for providing the main memory in the computer system.
- ROM cannot be easily modified, so they are fit to store the data which won’t require modification for a longer period of time. One can say that this type of memory is hard-wired, cannot be altered after its manufacture. A recent version of ROM has arrived, contain memory which is read-only for normal operation, although can be programmed. EPROM i.e. Erasable programmable read-only memory and EEPROM i.e. electrically erasable programmable read-only memory can be removed and re-programmed. However, this process takes time, relatively slower in speed and can be achieved at certain attempts.
- When the computer is powered on, a certain amount of memory is required, to run the initial program which is stored with ROM. This process is also known as booting or bootstrapping. In the modern computer, booting for the main processor is stored in ROM, other devices like a graphics card, hard disk, CD-DVD drives also utilizes ROM in the system. Mask-programmed ROM is the classical example of ROM, which physically encodes the data required to be stored. They are integrated circuits and impossible to change their content. Another category of ROM, however, can be modified, which includes PROM, EPROM, EEPROM. ROM, which is electrically modified, their reading speed is faster than the writing speed. After applying for write protection, some reprogrammable ROMs become read-only memory.
Head To Head Comparison Between RAM and ROM (Infographics)
Below is the top 6 difference between RAM vs ROM
Key Difference between RAM and ROM
Both are popular choices in the market; let us discuss some of the major difference:
- RAM is random access memory and cannot hold the data without the power whereas ROM is a read-only memory and can hold the data even without the power.
- RAM is volatile storage medium to store the information whereas ROM is non-volatile storage medium to store the data.
- With RAM, writing data is much faster and lightening process whereas ROM, writing data speed is much slower as compared to RAM.
- RAM comes in two flavors i.e. static RAM and dynamic RAM whereas ROM has three varieties like Mask ROM, PROM, EPROM, EEPROM.
- Data on RAM is accessed, read and erased multiple times whereas on ROM, writing data is a relatively very slow process.
- RAM has usage with primary memory DRAM and CPU cache memory SRAM whereas ROM is being used in BIOS, microcontrollers, and other electronic devices.
- RAM is expensive and does not come cheap whereas ROM is way cheaper as compared to RAM.
- RAM has large size with even higher capacity whereas ROM is smaller in size and even with lesser capacity.
- RAM is a high-speed memory, with reading-write operations, happen at a fast pace whereas ROM is slower speed memory, which is less prone to modification and can be done via an external program.
- With RAM, data on it can be altered multiple times, which explain its expensiveness whereas ROM has data, which is permanent, even though can be altered but at a very slow speed and that too, for a limited number of times.
RAM vs ROM Comparison Table
Below is the topmost comparison between RAM vs ROM
|The Basis Of Comparison||RAM||ROM|
|Data||RAM cannot hold data without power||ROM can hold data without power|
|Storage||A temporary medium of storage||A permanent medium of storage|
|Power||RAM chip is volatile, loses information if power is gone||ROM is nonvolatile, does not require a constant source of power|
|Operation||RAM chip is used in normal operation of a computer||ROM is primarily used in the startup process of a computer or bootstrapping|
|Speed||Writing data to RAM is faster||Writing to ROM is much slower as compared to RAM|
|Example||RAM chips can store information, run the program and quickly switch between the tasks||PROM chip used with BIOS store the program need to begin initial computer startup process|
In this RAM vs ROM article, we have seen both RAM vs ROM have their own set of merits and demerits. But both types of memory devices are mandatory for the efficient functioning of a computer device. ROM is cheap, can hold data permanently, but has its own set of limitation like hard to modify the data, and that too for a fixed number of time. RAM is expensive, but at the same time, data can be altered on it multiple times.
However, with a modern electronic landscape, ROM is no less incompetent. Removable storage media like USB drives, Storage data cards etc is a sophisticated implementation of EEPROM, a read-only memory. Thus, both RAM vs ROM are meeting the requirement of technologies and performance of applications, with a large volume of data processing.
This has been a guide to the top difference between RAM vs ROM. Here we also discuss the key differences with infographics, and comparison table. You may also have a look at the following articles to learn more