Minecraft started off as a small 3D sandbox game created using the Java language in 2009, and is to this day one of the most popular sandbox games that (almost) everyone has played. Its popularity and faithful community led the game to being able to extend beyond what it was originally and can be used for various purposes, such as creating cooperative or competitive game servers, teaching software programming, or even reaching as far as becoming a virtual reality game.
Raspberry Pi Edition
Minecraft was planned to have a Raspberry Pi edition that was worked on at some time in the past. The port was a fork of Minecraft: Pocket Edition 0.6.1's codebase at the time and was renamed to version 0.1. The version was unfortunately cancelled not long after development started but the official Raspberry Pi Operating System Raspbian still included the game in the flashable SD card image for a long time. While it was cancelled, people still made efforts to create mods for the game using python scripts, as the game could natively interact with the Python interpreter.
One of the major limitations of the game was the absence of survival mode, which while not available is fully functional. To access survival mode, the user would have to use a Minecraft Pocket Edition world for 0.6.1 and put it in their worlds folder for Raspberry Pi Edition. The survival mode was complete enough to even include night and day cycles, something absent from both Pocket Edition and Raspberry Pi Edition on creative mode (until the 0.10.0 update for mobile).
PC Gamer Demo
During Minecraft's beta stage, PC Gamer released a small playable demo that generated a map that included the PC Gamer demo logo in the distance and set a 100 in-game hour timed lockout (or 5 complete day-night cycles). The game lacked the option to play in creative mode and also lacked the ability to generate new worlds, however one can generate a new world by creating a new map in Minecraft beta 1.5 (or by using a Minecraft Server jar executable) and replace the world data inside the folder for the demo with the server's map. This does not however affect the timed lockout but allows the user to still play Minecraft.
Pocket Edition Demo
In the early days of Minecraft: Pocket Edition, a demo version of the game was offered which fairly limited what blocks users were allowed to place and what tools they could use to place them. The game also offered a tiny select amount of NPCs and forced the player to play on creative mode only. The demo went as soon as it came, and has not been updated past version 2.1. Due to the age of the Android SDK API level, the demo of the game is not optimized for Android versions later than 3.
An edition of Minecraft was released called Bedrock Edition which was specifically centered towards cooperative play and cross platform. Players with certain versions on platforms who were eligible received this version for free.