Popular Usage: In 1982, Andrew Fluegelman created a program for the IBM PC called PC-Talk, a telecommunications program, he used the term freeware. About the same time, Jim "Button" Knopf released PC-File, a database program, calling it user-supported software[2]. Not much later, Bob Wallace produced PC-Write, a word processor, and called it shareware.
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In the early 1990s, shareware distribution was a popular method of publishing games for smaller developers, including then-fledgling companies such as Apogee Software (now also operating under the brand 3D Realms), Epic Megagames (now Epic Games), and id Software. It gave consumers the chance to play the game before investing money in it, and gave them exposure that some products would be unable to get in the retail space.
With the Kroz series, Apogee introduced the "episodic" shareware model that became the most popular incentive for "registering" (or buying) the game. While the shareware game would be a truly complete game, there would be additional "episodes" of the game that were not shareware, and could only be legally obtained by paying for the shareware episode. In some cases these episodes were neatly integrated and would feel like a longer version of the game, and in other cases the later episode(s) would be stand-alone games.