This document provides an overview of computers and programming. It defines a computer as a programmable machine that requires programs to function. Computers can perform office work, entertainment, information access, education, online shopping, video conferencing and desktop publishing. A computer has hardware components like the system unit, input and output devices, and software like operating systems, programming languages and applications. The basic operations of a computer are to receive input, process data, produce output and store data/instructions. The machine cycle describes the basic process by which a computer retrieves and executes instructions, repeating continuously from startup to shutdown. The four steps are instruction fetch, instruction decode, instruction execution and instruction storage.