Microcomputers in the context of Commodore 64

An IBM PC compatible is any personal computer that is hardware- and software-compatible with the IBM Personal Computer (IBM PC) and its subsequent models. Like the original IBM PC, an IBM PC–compatible computer uses an x86-based central processing unit, sourced either from Intel or a second source like AMD, Cyrix or other vendors such as Texas Instruments, Fujitsu, OKI, Mitsubishi or NEC and is capable of using interchangeable commodity hardware such as expansion cards. Initially such computers were referred to as PC clones, IBM clones or IBM PC clones, but the term "IBM PC compatible" is now a historical description only, as the vast majority of microcomputers produced since the 1990s are IBM compatible. IBM itself no longer sells personal computers, having sold its division to Lenovo in 2005. "Wintel" is a similar description that is more commonly used for modern computers.

The designation "PC", as used in much of personal computer history, has not meant "personal computer" generally, but rather an x86 computer capable of running the same software that a contemporary IBM or Lenovo PC could. The term was initially in contrast to the variety of home computer systems available in the early 1980s, such as the Apple II, TRS-80, and Commodore 64. Later, the term was primarily used in contrast to Commodore's Amiga and Apple's Macintosh computers.

A computer terminal is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. Most early computers only had a front panel to input or display bits and had to be connected to a terminal to print or input text through a keyboard. Teleprinters were used as early-day hard-copy terminals and predated the use of a computer screen by decades. The computer would typically transmit a line of data which would be printed on paper, and accept a line of data from a keyboard over a serial or other interface. Starting in the mid-1970s with microcomputers such as the Sphere 1, Sol-20, and Apple I, display circuitry and keyboards began to be integrated into personal and workstation computer systems, with the computer handling character generation and outputting to a CRT display such as a computer monitor or, sometimes, a consumer TV, but most larger computers continued to require terminals.

Early terminals were inexpensive devices but very slow compared to punched cards or paper tape for input; with the advent of time-sharing systems, terminals slowly pushed these older forms of interaction from the industry. Related developments were the improvement of terminal technology and the introduction of inexpensive video displays. Early Teletypes only printed out with a communications speed of only 75 baud or 10 5-bit characters per second, and by the 1970s speeds of video terminals had improved to 2400 bit/s or 9600 bit/s. Similarly, the speed of remote batch terminals had improved to 4800 bit/s at the beginning of the decade and 19.6 kbps by the end of the decade, with higher speeds possible on more expensive terminals.

Gary Arlen Kildall (/ˈkɪldɔːl/; May 19, 1942 – July 11, 1994) was an American computer scientist and microcomputer entrepreneur. During the 1970s, Kildall created the operating system CP/M among other operating systems and programming tools, and subsequently founded Digital Research, Inc. to market and sell his software products. He is considered a pioneer of the personal computer revolution.

In 1974 in Pacific Grove, California, Kildall demonstrated the first working prototype of CP/M, which would later become the dominant operating system for microcomputers for a time. Together with his invention of the BIOS (Basic Input Output System), his operating system allowed a microprocessor-based computer to communicate with disk storage. Kildall was among the earliest individuals to recognize microprocessors as fully capable computers. During the 1980s, Kildall also appeared on PBS as co-host of Computer Chronicles, a weekly informational program that discussed the latest developments in personal computing.