Bedrock

Bedrock is a block that is indestructible in Survival.

Obtaining
Bedrock cannot be broken in Survival mode without glitches. $$, certain glitches can be used to obtain bedrock in Survival. $$ it is impossible to obtain bedrock using normal means, but it can be acquired with some difficulty, using multiple glitches at once. If you want to get bedrock without glitches in Survival, you have to turn Commands on and run the command /give @p bedrock 64 for a stack of bedrock.

Natural generation
Bedrock comprises the five bottom-most layers of the Overworld in a rough pattern, although the top four layers are predominantly flat bedrock with only rare gaps, rendering the lowest, completely flat fifth layer (at y=-64) mostly inaccessible. $$, the patterns of bedrock are consistent in all worlds regardless of world seed (except Superflat). $$, the patterns are dependent on the seed in the Overworld.

In the Nether, bedrock comprises both the top and bottom four layers in a rough pattern. In both Java and Bedrock Editions, the patterns of bedrock are consistent in the Nether. At the top of the Nether, bedrock prevents the player from ascending above y=127 without exploiting glitches, although $$ the build limit extends to y=255 like the Overworld and the End.

In the End, a single bedrock block generates on top of each obsidian pillar, each topped with an end crystal. The bedrock remains after the destruction of the crystal, and is lit on fire indefinitely. Bedrock additionally comprises part of the exit portal at the center of the central island. $$, if one manages to break the bedrock in the exit portal, the bedrock reappears when the portal regenerates. Placing an end crystal on Bedrock in the end will set it on fire.

An End gateway is generated upon the death of each ender dragon, each containing 12 blocks of bedrock. A total of 20 of these portals generate in a circle around the central island in set positions. A corresponding end gateway is generated in the inner edge of the outer islands after an end gateway on the main island is activated. Additional end gateways also generate randomly across the outer End islands.

Info
Bedrock's primary usage is as a solid unbreakable block to prevent players from falling into the void.

Mobs also do not spawn on bedrock. Endermen are unable to place the block they are holding onto bedrock.

Additionally, when set on fire in the End, the fire on bedrock never extinguishes naturally, similarly to the fire on netherrack.

Trapping Wither
Since bedrock is indestructible in Survival, even by boss mobs like the wither, certain configurations of bedrock can be cleverly used to securely trap the wither (or even multiple of them) by spawning them below the bedrock. The wither can then be either easily killed, or utilized to break blocks automatically, or farm wither roses.

Note Blocks
Note Blocks can be placed above Bedrock to produce "bass drum" sounds.

Piston interactivity
Bedrock is unable to be pushed or pulled by either of the piston variants.

ID




Block states
$$, bedrock uses the following block states:

Trivia

 * Strongholds can cause bedrock not to form within its bounds.
 * The bedrock texture, regardless of the current default resource pack (Programmer Art or Default), is basically the stone block with really high contrast.
 * Vexes and the ender dragon can fly through bedrock. Additionally, the ender dragon cannot break bedrock.
 * The largest clump of Bedrock at its top-most layer is located at X=21,783,512 Z=-800,011.
 * Outside of Minecraft, "bedrock" just means any solid rock beneath the soil layer (So everything below the dirt, sand, or gravel surface).