RAM (random access memory)

RAM (random access memory) is the place where the operating system, application programs, and data in use are stored so that they can be quickly access by the computer's processor. RAM is considered to be faster to read from and write to than the other available storage in a computer such as the hard disk, floppy disk, and CD-ROM. The data in RAM stays there as long as your computer is running or turned on. When you unplugged your computer off, RAM loses its data. When you turn your computer on next time, your operating system and other files are once again loaded into RAM, generally from your hard disk.

RAM is also known as "random access" because any storage location can be acheived directly. Originally, the term discriminates regular core memory from offline memory, commonly on magnetic tape in which an item of data could only be gained by starting from the beginning of the tape and finding an address sequentially. Perhaps it should be termed as "nonsequential memory" because RAM access is hardly random. RAM is organized and controlled in a way that permits data to be stored and retrieved directly to particular locations. You sholld note that other forms of storage such as the hard disk and CD-ROM are also accessed directly but the word random access is not applied to these types of storage devices.

Commonly RAM are of two types: DRAM (Dynamic Random Access Memory) and SRAM (Static Random Access Memory). The two types of RAM differ in the way they use to hold data, with DRAM being the more common type. When it comes to speed, SRAM is faster. DRAM needs to be refreshed more than SRAM. SRAM has the advantage that it does not need to be refreshed, what makes it faster than DRAM. DRAM technology supports access times nearly about 60 nanoseconds, SRAM can give access times as low as 10 nanoseconds. Despite SRAM being faster, it's not as commonly used as DRAM because it's too much expensive. Both types of RAM are volatile, which means that they lose their data or the contents when the cable is unplugged.