The three main components are cpu (central processing unit), memory storage devices (ram), and hard disk drives. Cpus process data from memory storage devices as well as from other cpus within one system. Memory storage devices store programs, data, and other information needed by cpus. Hard disk drives store programs, data, and other information needed by cpus. Cpus communicate with each other via buses which transfer data between different types of memory storage devices such as rams etc. . a motherboard contains all these