Spawn

Spawning refers to players and mobs being created and placed in the game world. Players will respawn on their spawn point upon death.

Spawn Point
Every world created has a spawn point which is located at coordinates x=0.5, z=0.5 and the highest possible Y by default. The player's first view of the map will be from the spawn point, facing east. In the current version, the spawn point can only be on sand. If you generate a world with a seed, the chances are you won't start at 0.5, 0.5

It is possible to move the spawn location with the use of a Map Editor, if you do not want to use a map editing program there are limited ways to move the spawn through the use of game mechanics. For example, if the spawn point is occupied by a solid block the player will spawn at the closest 1x1x2 open space directly above the spawn point. This means a player can build a 1x1 tower in the spawn point to move the spawn upward as long as the tower still exists. The spawn location can also be moved horizontally if the player digs four spaces downward from it. However, this will only move the spawn point a few blocks away from the original position; it is not possible, using this method, to dramatically or controllably alter the location of the spawn point. Beds, which were added in Beta 1.3, may eventually be used as spawn points.

Players can find their spawn point in game by using a compass, or simply by dying and seeing where they show up.

In Beta multiplayer, rather than spawning on top of a single spawn block, players will instead spawn on top in a spawn area of around 20x20 tiles. The spawn area along with a 13 tile border is classed as a protected area, this means non-op players cannot place or destroy blocks in this protected area nor can they use doors or Redstone devices. Creepers can still destroy terrain in the protected area and TNT placed outside of the protected area will destroy surrounding blocks as usual. The protected area is 46x46 tiles and the spawn area(20x20 tiles) is in the centre of this area.

Mobs
Mobs spawn no closer than 24 blocks, but no further than a 144 x 144 area around the player's location after a short delay. A player running through the game world will usually keep ahead of the waves of mobs spawning. Mobs are removed if they become more than four chunks away from the player.

Passive mobs
Passive mobs will spawn in grassy areas with a light level of more than 9. Chickens also have a 1/8 chance of spawning from a thrown egg.

Enemy Mobs
Enemy mobs can spawn on any fully-opaque cube block with a light level of less than 7. They will not spawn if difficulty is set to 'Peaceful', and they never spawn on Glass, Ice, Stone Slabs, or other see-through or non-cube blocks. There are also Monster Spawners in dungeons that are a fixed spawn point for enemy mobs.

Since the graphics mode affects whether Leaves are see-through, it also affects spawning behavior: on 'Fast', mobs will spawn on leaf blocks; on 'Fancy', they won't. Mob spawning on multiplayer servers always behaves as though the graphics mode is set to 'Fast'.

In The Nether, Ghast and Zombie Pigman spawning is independent of the light level.