RAM stands for Random Access Memory. When a layman refers to a computer’s memory he or she is actually talking about the Random Access Memory, or the RAM. It is the RAM that actually forms the layer between the Operating System and the application such that the application is loaded onto the Random Access Memory and then it executes all the necessary functions from the RAM itself. Thus the RAM is called the Primary memory of a computer system – all the memory storage and access modules are secondary to the primary memory since without the primary memory’s heap, the computer will not work.
This memory is referred to as “Random Access” because unlike magnetic tapes, hard drives and optical storage devices, the data can be stored in any random cell as long as it is not filled and the row and column (that is, its coordinates) is known to the processor via the application. The RAM can also be thought of as a “heap” of memory which is large and well defined and can take as much input per processor cycle as its memory capacity is. Thus, since RAM is very expensive, it comes in packages of 512MB or 1GB or 2GB. The power required by the RAM is also very high, and thus a really large amount of RAM is not feasible for home computers.
RAM is a type of volatile memory. That is to say, its memory contents vanish the moment the power to it is lost. Each cell of the RAM module needs a constant power supply to store and put up for access their data. That is why secondary memory modules exist that store the data in them without the need for a constant power supply to keep the data there. Some types of RAM also store data in them for a specific period of time before wiping it out.
RAM is also necessary for the basic operations of switching on and off the computer and accessing the Operating System. When the power is switched on, the Basic Input/Output System (BIOS), the PC’s firmware reads data relating to the Operating System and the computer’s default configurations and loads all that data onto the RAM. The RAM is the starting point of all functions in a computer, and thus it starts the computer by providing for all the data it needs from the randomly allocated and accessed heap. For various jobs, various types of RAM’s are used.