Logic manufactures have produced 'large scale' logic (LSI) blocks to achieve complex functions; a typical set of logic functions is that of data storage. There are two main types of storage:
 
    1. Volatile (Require voltage to hold data)
    2. Non volatile (Do not require voltage to hold data)
 
The most common volatile memory is the RAM device. There are two basic types of RAM: Static (SRAM) and Dynamic (DRAM). SRAM consists of MOSFET's wired up in flip-flop mode, if they are set; the data is logic '1', or reset logic '0'. Shown overleaf are the pining details of a basic SRAM device.

By looking at the internal structure shown below, we can see that the design employs decoders and other basic logic systems.