This article covers computer software designed to solve, or assist people in creating or solving, chess problems – puzzles in which pieces are laid out as in a game of chess, and may at times be based upon real games of chess that have been played and recorded, but whose aim is to challenge the problemist to find a solution to the posed situation, within the rules of chess, rather than to play games of chess from the beginning against an opponent. This is usually distinct from actually playing and analyzing games of chess. Many chess playing programs also have provision for solving some kinds of problem such as checkmate in a certain number of moves (directmates), and some also have support for helpmates and selfmates. Software for chess problems can be used for creating and solving problems, including checking the soundness of a concept and position, storing it in a database, printing and publishing, and saving and exporting the problem. As such they can not only solve direct mates, helpmates and selfmates, but at times even problems with fairy pieces and other fairy chess problems. There have also been some attempts to have computers "compose" problems, largely autonomously. Software Alybadix First developed in 1980 by Ilkka Blom, Alybadix is a suite of chess problem solving programs for DOS and Commodore 64. Alybadix supports solving classical problems: selfmates, reflex mates, series mates, Circe, maximummers, and many Fairy types. It comes with a large problem collection and supports quality printing. In 1993, Schach und Spiele magazine considered Alybadix to be six times faster than other playing machines including the RISC 2500. Popeye Popeye is a chess problem-solving software accommodating many fairy chess rules and able to investigate set play and tries. It can be used with several operating systems and can be connected to several existing graphical interfaces since it comes with freely available source code, cf. . Since its origin, Popeye was designed as a general-purpose, extensible tool for checking fairy and heterodox chess problems. The original author of Popeye was Philippe Schnoebelen who wrote it in Pascal under MS-DOS around 1983-84. In 1986 the code was donated in the spirit of the free software movement. Elmar Bartel, Norbert Geissler, Thomas Maeder, Torsten Linss, Stefan Hoening, Stefan Brunzen, Harald Denker, Thomas Bark and Stephen Emmerson, converted Popeye to the C programming language, and now maintain the program. A good graphic