L'ordinateur personnel se confond aujourd'hui avec le micro-ordinateur ou ordinateur individuel : c'est un ordinateur destiné à l'usage d'une personne et dont les dimensions sont assez réduites pour tenir sur un bureau. La première machine appelée micro-ordinateur fut le Micral N, breveté en 1973 par le français François Gernelle. Toutefois on pouvait déjà considérer comme ordinateurs personnels les mini-ordinateurs diffusés au cours des années 1960, ainsi que la calculatrice de bureau Olivetti Programma 101 commercialisée en 1965.
The Macintosh Portable is Apple Inc.'s first battery-powered portable Macintosh personal computer. It was also the first commercial off-the-shelf portable computer used in space and the first to send an email from space, in 1991 aboard Space Shuttle mission STS-43.
Released on September 20, 1989, it was received with excitement from most critics but consumer sales were quite low. It featured a fast, sharp, and expensive black and white active matrix LCD screen in a hinged design that covered the keyboard when the machine was not in use. The Portable was perhaps the first consumer laptop to employ an active matrix panel, and only the most expensive of the initial Powerbook line, the Powerbook 170, used one, due to the high cost. The cursor pointing function was handled by a built-in trackball that could be removed and located on either side of the keyboard. It used expensive SRAM in an effort to maximize battery life and to provide an "instant on" low power sleep mode. The machine was designed to be high-performance, at the cost of price and weight.