Random Access Memory

                               Random-Access Memory         

Random-access memory (RAM) is a Device which allows data to read as well as write.RAM is a basically a  form of computer data storage.
In contrast, with other direct-access data storage media such as hard disks, CD-RWs, DVD-RWs and the older drum memory, the time required to read and write data items varies significantly depending on their physical locations on the recording medium, RAM is basically used in computer or electronic gadgets now days.

RAM are of two types:

1.SRAM(Static Read Only Memory)

2.DRAM (Dynamic Read Only Memory)

Random-access memory takes the form of integrated circuits. Modern types of DRAM are not random access, as data is read in bursts, although the name DRAM / RAM has stuck. However, many types of SRAM are still random access even in a strict sense. RAM is normally associated with volatile types of memory (such as DRAM memory modules), where stored information is lost if the power is removed, although many efforts have been made to develop non-volatile RAM chips.

Difference between SRAM & DRAM

1. DRAM requires the data to be refreshed periodically in order to retain the data. SRAM does not need to be refreshed as the transistors inside would continue to hold the data as long as the power supply is not cut off. 
2. The additional circuitry and timing needed to introduce the refresh creates some complications that makes DRAM memory slower and less desirable than SRAM .
3. SRAM needs a lot more transistors in order to store a certain amount of memory. A DRAM module only needs a transistor and a capacitor for every bit of data where SRAM needs 6 transistors .