Computer Architecture in general covers three aspects of computer design namely: Computer Hardware, Instruction set Architecture and Computer Organization.

Computer hardware consists of electronic circuits, displays, magnetic and optical storage media and communication facilities. Instruction set Architecture is programmer visible machine interface such as instruction set, registers, memory organization and exception handling. Two main approaches are mainly CISC (Complex Instruction Set Computer) and RISC (Reduced Instruction Set Computer)

Computer Organization includes the high level aspects of a design, such as memory system, the bus structure and the design of the internal CPU.