Software: any program or group of programs which instructs the hardware on how it should perform, including operating systems, word processors and applications programs.

(Collin, S.M.H. [ed.], Dictionary of Multimedia, Peter Collin Publishing, Teddington, Middlesex, 1995, p241)

There is generally more money to be made in software than hardware - since each computer user tends to use many different programs - which explains Microsoft's domination of the computing market. This in turn has helped to explain the predominance of the IBM-compatible PC over the Apple Mac, since most software programs are made for the IBM-compatible machines only.