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+RRace is a slide puzzle racing game.  The goal is to re-arrange coloured tiles
+in the game area to create the objective pattern as quickly as possible.
+
+The game is inspired by Rubik's Race, a board game for two players that dates
+back to the Rubik's Cube craze in the early 1980s, which you can apparently
+still buy in 2022.
+
+# Prerequisites
+
+RRace is written in C, so a working C compiler is compiled.
+
+To build the UI for X11 systems, the [Motif toolkit][motif-homepage] is
+required.
+
+Optionally, in order to support localized program messages the [GNU libintl
+library][gettext-homepage] (included wit the GNU C library) is required.
+
+[motif-homepage]: https://sourceforge.net/projects/motif/
+[gettext-homepage]: https://www.gnu.org/software/gettext/
+
+# Playing the Game
+
+The game is played on a 5x5 grid of tiles, called the *game area*, containing
+24 tiles in 6 different colours--4 of each colour.  There is one *empty
+position* in the game area.  The *goal area* is a 3x3 grid of tiles which
+displays the *objective* pattern that must be formed to win the game.
+
+Selecting a tile in the same row or column as the empty position will "slide"
+that tile, along with any tiles between it and the empty position, into the
+empty space.  The new empty position will be at the selected location.  Such
+moves are repeated until the colours in the centre 3x3 subgrid of the game
+area match the objective.
+
+Since there are four tiles in each colour, any of those tiles may be used
+to match any of the corresponding positions in the objective.  Together with
+the fact that only a portion of the game area needs to be solved, this makes
+the game considerably easier than a more traditional slide puzzle.
+
+# Contributing
+
+Please send suggestions, bug reports, patches or any other
+correspondence regarding RRace by electronic mail to
+[Nick Bowler \<nbowler@draconx.ca\>][email].
+
+[email]: mailto:nbowler@draconx.ca
+
+# License
+
+RRace is free software: you can redistribute it and/or modify it under the
+terms of the GNU General Public License as published by the Free Software
+Foundation, either version 3 of the License or (at your option) any later
+version.
+
+{::comment}
+Copyright © 2022 Nick Bowler
+{:/comment}