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.
