Different Types of RAM & ROM

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When your computer executes a task prompted by a user, it undergoes a series of processes which require access to various forms of memory. Computer memory is a term which can define any hardware device that retains information for either short or long periods of time within a computing system. The two primary forms of memory used in computers are Random Access Memory, or RAM, and Read-Only Memory, or ROM. Both RAM and ROM work together to optimize a user's computer experience, ensuring that he has the resources available to complete their desired tasks. Interestingly, both RAM and ROM are terms which encompass a wide array of hardware variants. Taking the time to identify the different types of RAM and ROM can help you gain a better understanding of this unique element of modern computing.

Identifying Different Types of RAM

There are several different forms of RAM in use today within the world of computing. Static RAM (SRAM) and Dynamic RAM (DRAM) are considered the two primary variants in use. Static RAM requires a constant power source during operation and can store data indefinitely without any form of refreshing. This contrasts significantly with DRAM, which must be routinely recharged due to the fact that the onboard capacitors will slowly lose their power. If all power is lost, the DRAM will lose all data being stored within it. Both SRAM and DRAM are considered to be "volatile memory." Volatile memory sources release all data stored on them when the power being supplied to them is cut off.

Identifying Different Types of ROM

Unlike RAM, which allows users to quickly write and rewrite content as needed, ROM is typically used for storing data that will not be changed and, instead, simply read. A unique feature of ROM is that it can retain data stored within it even when the power being supplied to it is removed. Two of the most common forms of ROM are programmable read-only memory, often referred to as PROM, and erasable programmable read-only memory, or EPROM. As you can tell from their titles, the primary difference between PROM and EPROM is the ability to erase data stored on them. Data stored within EPROM hardware can be removed when it's exposed to ultraviolet light. Once data is stored within PROM, however, it can't be removed.

Volatile and Nonvolatile Memory

One of the most important distinctions to account for when discussing computer memory is volatile vs. nonvolatile memory. Whereas volatile memory, such as the RAM discussed here, loses the data stored within it following a loss of power, nonvolatile memory such as EPROM and PROM will continue to store data placed on them even after a connection to power is lost.