RAM

RAM, short for Random Access Memory is the short storage area for your PC. Often just called memory or system memory RAM is just an electromagnetic storage that loses all its data once the power has been removed. RAM is used by your operating system and other programs and games in order to store data that is required at speed. Computers with large amount of memory often perform faster simply because the CPU is not idle waiting for data to be retrieved from slower components such as the hard drive and can be stored in memory.

RAM can be accessed by the computer for any piece of data in any cell of the memory bank. There is no need to go through the entire memory bank to get to the data you require. The opposite to Random access is serial access. SAM or Serial Access Memory needs to be read from the start to get to the data you require. An example of SAM storage would be a cassette tape. Of course there are things which fit in-between these two examples such as a CD or DVD. Because these have tracks they can be random access to a point but then need Serial access to get to the exact spot required.

RAM consists of many capacitors and transistors. A capacitor and a transistor are paired together to make a memory cell. The capacitor represents one "bit" of data, the transistor is able to change the state of the capacitor to either a 0 or a 1. the Zero's and ones when read in a sequence represent the code which the computer understands. This is called binary data because there is only two states that the capacitor can be in.

In order for a capacitor to achieve a value of 1 it needs to be filled with electrons. To achieve a value of 0 the capacitor needs to be emptied of electrons. You may of noticed when purchasing RAM that many types of RAM you buy are called DRAM or SDRAM. DRAM or Dynamic Random Access Memory has a small problem with the capacitors holding a value of 1. It is called dynamic RAM because its state of 1 or 0 needs to be constantly refreshed on order to stay in the correct state. In order to demonstrate this and for a much more detailed look into the workings of RAM a good site site is how stuff works. This article will show you a much more technical look at the workings of RAM and has a great Diagram to illustrate the nature of Dynamic Random Access Memory

There is a type of RAM that doesn't have to be refreshed constantly. This is called SRAM or Static RAM. Static RAM uses a type of Flip Flop to hold the data in the cell. This can take around 6 transistors on a chip per cell rather than just the one., The consequences are that Static RAM needs more chips per Mb than DRAM and therefore is much more expensive.