Invideo games usingprocedural world generation, themap seed is a (relatively) short number or text string which is used to procedurally create the game world ("map"). This means that while the seed-unique generated map may be many megabytes in size (often generated incrementally and virtually unlimited in potential size), it is possible to reset to the unmodified map, or the unmodified map can be exchanged between players, just by specifying the map seed. Map seeds are a type ofrandom seeds.
Games which use procedural generation and include support for setting the map seed includeArk: Survival Evolved,Minecraft,Factorio,SCP – Containment Breach, and the desktop version ofTerraria. ForMinecraft especially, there are websites[1][2][non-primary source needed] and articles,[3][4] dedicated to sharing seeds which have been found to generate interesting maps.
The map seed only has meaning in the context of the algorithm used to generate the map (that algorithm is often,[5][6] based onPerlin noise). So if the map generation algorithm changes, the map generated by a given seed will also change. Such changes are particularly obvious inMinecraft, where they are handled (or rather, not handled) by simply generating any newly explored chunks of an existing map using the new algorithm, leading to obvious and jarringdiscontinuities after upgrading.
Favorable seeds can be used whenspeedrunning video games by specifying the map seed manually.