Shareware is a trial version of a program, posted by a vendor on the Internet. The version may not possess all the capabilities of the final version. Users who approve of the trial version may be induced to send payment once the final version is available. Freeware is software that is available for free on the Internet. In recent times, the most well-known example of freeware has been the Linux operating system.

In the 1970s, when the computer user community was small, user-written programs were routinely circulated among users. Following the introduction of the International Business Machine personal computer in 1981, the number of users skyrocketed, making such communal sharing of programs not feasible. The following year, two programmers, Andrew Fluegleman and Jim Knopf wrote a communications program and a database program, respectively, for use on the IBM PC. They decided to distribute these programs...