NetHack is a single-player turn-based roleplaying game. The player creates an character that starts a quest for 'The Amulet of Yendor'. It is presented originally in a text-based mode, every ASCII-character represents an object or a character of the game and with the characters a map is created. Modern NetHack-variants also include a graphical tileset. Originally the game was released 1987, the actual version is 3.4.3. NetHack is an Open-Source-Game and available for free download under http://www.nethack.org/.