Tile map is a technique of re-using small graphic pieces, tiles, over and over again to shape the game field.
The typical tile map consists of a 2-dimensional array/matrix containing references to a tile object. This tile object holds information such as the type of terrain, if it is possible to walk on it, if it causes damage to the video game character etc., as well as the identity of the graphic to be rendered whenever that tile is to be drawn.
This approach allows for simple, visual map data, letting level designers create entire worlds with a simple text editor and a tile reference sheet, though most if not all accomplished tile-based games utilize dedicated world editor software and highly optimized map formats.
