The Void is the term given to the empty space beyond the bedrock layer in the Overworld, Nether, and End (for the End, below the island). The Void appears at the bottom of maps, where layers of bedrock restrict access to it. The Void is technically endless, however if you fall more than 32 million blocks down, Minecraft will crash. Falling into the Void and the
/kill command are the only possible ways to be killed in Creative mode. 
Blocks cannot be built on the underside of the Bedrock layer, but if Gravel or Sand are placed in the bottom hole nearest the void, they will fall infinitely. Pistons don't extend if placed facing downward at Y=1 and won't extend if placed at Y=0, so blocks can't be pushed into the void. Although Water and Lava appear to flow into it, they will not actually spread and form beneath the lowest layer. This prevents players from descending into the Void safely via swimming. It also prevents extreme lag; if the liquid were to flow down infinitely the game would have to deal with the hefty amount of water/lava blocks in the game which would eventually crash.
The Void is unique in the way it gives off fog in a visual effect, generally known as the Void Fog Effect. When close to the void, the player will experience shortened range of vision if in survival/adventure mode, due to 'fog' given off by the Void dimension itself. Regardless of the render distance selected by the player, this effect will still be experienced, getting gradually more prominent every time the player descends one layer. This will not affect mob spawning, it is simply a visual effect. Black fog also closes in at high altitudes, though not as much.
In the Nether, the Void appears a reddish color. On top of the Nether, you can place blocks up to Y=255, unlike the Void in the Overworld or below the Nether. This is because the increase in maximum build height has not yet increased the height of the ceiling in the Nether. Lighting is buggy, mobs will not spawn on bedrock, and mushrooms spawn.
There is currently a bug in SMP that will remove chunks client-side, so while the data is still there, the client cannot see it and will glitch if they step on it. This can be fixed by reconnecting or placing a torch next to the missing chunk. If you ride a Minecart into this missing chunk, and then you step out of the Minecart, you will fall to the Void and die, regardless if you disconnect and reconnect.
 Entering the void
Falling into the Void past Y=-64 causes the player's health to be depleted by about every half second, leading to the player's death in 2.5 seconds or less, should he or she drop. Armor does not protect you from dying in the Void, and death always occurs at Y=-199.10. After this, if the player does not press any buttons, they will usually fall until somewhere below Y=-256, with this number varying on each death. However, if health or regeneration potions or golden apples are used the death level alters only slightly. If mods are used to make the player invincible or give them infinite health, they will fall until Minecraft crashes. When you fall into the void on a server with anti flying measures, you are kicked out regardless of having a flying mod. Riding a vehicle (e.g. Minecart) into the Void will result in the player being stuck in the vehicle until he/she dies.
Entities (mobs and items, excluding the player) will fall through the Void and receive the same damage as the player ( per half second), with the exception of the Wither which appears to take tremendous damage. All entities will disappear at Y=-64. Any entity above layer Y=319 or below layer Y=-64 will be black. Chickens can be spawned in the void using eggs (however they will die at Y=-64 like all other entities) and Primed TNT can fall into the Void and explode.
Entering the Void is not possible in the Pocket Edition. When you fly through the bedrock you die, even in creative. You are able to go into the Void in the Xbox 360 Edition. In the Pocket Edition, if one creates and activates a Nether Reactor on bedrock level a hole will be made in the void. Bedrock appears invisible from under, giving an effective X-ray machine, and the void itself is blue. The bedrock can also be mined in creative mode, giving some more ways to get to the void. However, the void cannot be accessed in the free version. Any entities in the Void are invisible, except for smoke particles from your corpse, which are black.
 Ways of reaching the Void
- Set your gamemode to Creative and dig straight down. It is possible to fly around in the top layers of the Void without taking damage.
- Plant 4 dark oak saplings underneath a dark oak tree already planted with the 4 blocks on the bottom missing. This will cut through the bedrock, and attempting to cut the tree will send you to the Void.
- Creative - dig straight down. Digging straight up will just put you on a layer of Bedrock. You can then build on this surface up to the building limit.
- Survival - Bring at least 2 Ender Pearls and navigate to the upper-most layer of bedrock you can find. Throw them at a steady pace upward onto the bedrock until teleporting on top of the layer of bedrock. Another way which only costs 1 Ender Pearl is to place a ladder below the upper-most layer of bedrock, and any solid block under the ladder. Throw an Ender Pearl to the ladder and hold the jump and forward button.
 The End
- Jump off the land. This will immediately drop you into the Void.
You can also dig straight down on the land. This will cause you to fall into the Void and die, since no bedrock will save you. If you make a staircase down, you can maybe make bridges in the Void, since in the end directly below the end island isn't directly where the void starts.
 Superflat world
- If you create a superflat world without bedrock layer, you can dig down to the last layer and jump into the void
|The Void acts and provides damage as an invisible lava sea, and making the lava only visible when entering the Void.|
|1.6||Prior to this update, things that fall into the Void would become black because there is no lighting there.|
|1.8||Void fog was added. If you are in within 16 blocks of the Void, the particle effect will be visible, along with limited visibility, as if you were on render distance tiny.|
|If using an X-Ray mod, you can see the color of the Void change from blue to black while descending. This can also be seen by a player in an ocean biome. Just before the player's head goes under the water, the horizon is seen to turn black, and as the player rises it changes back to blue.|
|Entities are now lit in the Void.|
|The Player can now reach the Void through Creative mode.|
|Previously, it was possible to find holes in the bedrock that lead into the Void. This was fixed.|
|Previously, if one was to pass the 32 million block limit (called the Far Lands), the player would no longer clip (the blocks become non-solid) and fall through to the Void, resulting in the player's eventual death. As of 1.8, at the 32 million block limit world generation becomes simpler and block physics fail.|
|1.1||11w48a||Before this update, the Void fog was in all game modes. Now, mobs and items that fall through the Void will receive the same damage as the player (2 hearts per second) and disappear, respectively, when they reach Y-64.|
|1.2.1||In maps generated prior to 1.2, it was still possible to find holes in the bedrock leading to the Void under very low-level lava pools. This was fixed, and holes in bedrock no longer exist.|
- If you open a hole to the Void and block off all light sources, you can see that the Void does in fact give off light (actually, it is the blocks themselves having a light level higher than 0, not the Void emitting light, as it appears to be). However, the bottom of the bedrock on the last layer is completely black.
- When the player is at a Y coordinate above 63, the Void appears blue, and the black fog is not rendered. When the player is at a Y coordinate below 63, the Void will change color to black and the fog will get closer to the player.
- In a Superflat world, sitting tamed wolves falling into the void will reappear next to you, taking little damage.
- In Superflat, however, the sky-blue Void is visible until Y=0. (This is not true. The void fog is only visible if there is no sunlight touching the player. If you make a 1x2 room on ground level in superflat, you WILL see void fog.)
- As of 1.2.5, Sunlight removes the Void fog, allowing for full visibility.
- Shot arrows can stick to the bottom of the lowest level of bedrock (they are stuck on a block in the Void).
- Flaming Arrows (arrows that have gone through lava or that have been shot from a flame enchanted bow) will disappear once they enter the Void while normal arrows fired by the player do not immediately disappear.
- Water and/or lava cannot flow into the void.
- If you destroy bedrock in creative mode and replace it with another block, particles, such as rain, will still fall through that block.
- The Void looks similar to the sky with the Night Vision status effect but if you enter the Void with the Night Vision effect, everything turns black.
- When falling into the Void, the sky above only renders for the current chunk. This can easily be tested by falling off on a skyblock world.
- When viewed on a map, the Void is seen as the pattern used for an unexplored area. This is because there are no blocks recorded in the Void's area, just the same as if you haven't explored or recorded normal areas.
- In the Xbox 360 Edition, you cannot fall into the void as of the 1.3 update, you would just stand on it without falling.
- The same thing happens at Y=511, you can't fly any higher.
- If someone joins a server with high latency, it can look like they spawned inside the Void, as the chunks have not generated yet. The Void can glitch between the old blue-sky Void and the new black Void (Void fog).
- When falling below Y=0, the second last line of the debug screen disappears entirely.
- If you give yourself both Regeneration and resistance at a level of IV or higher (Possible via hacks/mods/Commands) you will not die until the effects wear off. Also, some mini-game servers that have a spectate option that gives full invincibility rather than creative, enabling you to fall to Y=-32000000, crashing the game.
- In the Nether, the Void is on the top and the bottom.
- In Pocket Edition, you can visit the Void. In Creative, you can't break bedrock, though in 0.4.0 you can destroy bedrock and so fall into the void. Also, you can strip away the bottom layer of Bedrock by planting a Nether Reactor there. The pocket edition void is near the same as the PC version and the void does not change color from blue to black. Also, any blocks placed at y=0 are transparent, giving you an effective X-ray.
- Mineral blocks, cobblestone, stone, and other blocks have the same sound as bedrock.
- Minecraft 4k's generated world could be considered as "The end of the Void" for some players, since the sky is black and the "invisible bedrock" at the bottom of the map is black.
- You can glitch in a server; if the chunk is not loaded you can walk on The Void. When it loads, you are teleported back to the area where you jumped into it.
- The void can be found on top of the Nether, as stated before, but it only starts at Y=126, allowing you to continue building on top of the nether to y=255 or whatever the building limit is for a server.
- Falling off of the End Island is the only way to reach the Void 100% legitimately.
- You can survive falling into the Void by eating multiple Enchanted Golden Apples.
- The void beyond the end of the world(32,000,000 blocks from spawn)has a lot of gray particles floating about.
- The void actually isn't a huge open space. When falling into the void, you are actually falling into a sky-like place with a black box constantly around you, making it seem like the entire area is black and open. If you press F5 when falling into the void, you can see the sun/moon (depending on if its night/day) and the black box around your character. The black box goes wherever you go, and is filled with Void Particles. This is why other players and mobs turn black when they fall into the void (because you are seeing them through the black box). The black box starts at Y=64, and the void above that is actually a huge open space. This is why when you look up when falling into the void, it looks like a huge black tunnel is above you.
- The ability to fly around in Pocket Edition's Void was reported as a bug and since then players die as soon as their head is level with y=-1.
- In superflat, there is a preset called Bottomless Pit that has no bedrock, only cobblestone. This allows players to access the void in all 4 gamemodes.