Welcome to Allegro.pas
Allegro.pas is a wrapper that allows to use the Allegro game programming library with Pascal and Object Pascal compilers as Free Pascal and Delphi (including the Community Edition).
Allegro is a cross-platform library mainly aimed at video game and multimedia programming. It handles common, low-level tasks such as creating windows, accepting user input, loading data, drawing images, playing sounds, etc. and generally abstracting away the underlying platform. However, Allegro is not a game engine: you are free to design and structure your program as you like.
You can download a Game Demo (Windows and WineHQ), a simple game that shows some of the capabilities of Allegro.pas. Such a simple game isn't enough to show everything that Allegro can offer. If you want to know more about what you can do with Allegro.pas, take a peek to the documentation.