Eventually, DRAM was introduced. A DRAM unit is a type of integrated circuit containing huge banks of an electronic component called a capacitor which can store an electrical charge for a period of time.
The first IC's contained a few tens of components; as of 2006, the Intel Core Duo processor contains 151 million transistors. Along with its portable equivalent, the laptop computer, the personal computer is the ubiquitous information processing and communication tool, and is usually what is meant by "a computer".