Volatile memory

Volatile memory, contrary to non-volatile memory, is computer memory that requires power to maintain the stored information; it retains its contents while powered on but when the power is interrupted, the stored data is lost immediately or very rapidly.

Volatile memory has several uses - for example, as main memory. In addition to usually being faster than forms of mass storage such as a hard disk drive, volatility can protect sensitive information as it becomes unavailable on power-down. Most of the general-purpose random-access memory (RAM) is volatile.^[1]

There are two kinds of volatile RAM: dynamic and static. Even though both types need continuous electrical current for proper functioning, there are some important differences between them.

Dynamic RAM (DRAM) is very popular due to its cost effectiveness. If a computer has 1 gigabyte or 512 megabytes of RAM, the specification describes dynamic RAM (DRAM). DRAM stores each bit of information in a different capacitor within the integrated circuit. DRAM chips need just one single capacitor and one transistor to store each bit of information. This makes it space efficient and inexpensive.

The main advantage of static RAM (SRAM) is that it is much faster than dynamic RAM. Its disadvantage is its high price. SRAM does not need continuous electrical refreshes, but it still requires constant current to sustain the difference in voltage. In general, SRAM needs less power than DRAM, even though the power requirements differ based on the computer's clock speed. At moderate speeds SRAM usually requires just a fraction of the power used by DRAM. When idle, the power requirements of static RAM are low. Every single bit in a static RAM chip needs a cell of six transistors, whereas dynamic RAM requires only one capacitor and one transistor. As a result, SRAM is unable to accomplish the storage capabilities of the DRAM family.

SRAM is most commonly used in networking devices, like switches, routers, cable modems, etc., for buffering the transmitted information.

The physical structure and electronic properties of volatile memory makes it faster compared to electro-mechanical storage devices such as hard drives, which makes it an ideal candidate as the computer's main form of memory.

In terms of security, volatile memory is very secure since it does not retain any record at all after power is removed, so no data can be salvaged. However, this is a double-edged sword since all data is lost if there is power interruption.

See also

• Dynamic random-access memory (DRAM)
• Static random-access memory (SRAM)
• Integrated-random-access memory (IRam)

References