Block

Minecraft is composed of and built entirely out of blocks. They are the basic unit of Minecraft. You dig through blocks, you build with blocks, and your character is made of blocks – they are everywhere. It is possible to change how the blocks appear by applying new Texture Packs.

The face of a block is 16x16 pixels, and each block is proportionately one cubic meter. Water, Lava and Portal blocks have a shifting pattern for each face.

Types of Blocks
There are currently over 100 different types of blocks (including Air, still Water, and still Lava, which cannot be built at the moment, various types of Wood, various colors of Wool, various types of Pressure Plate, Slab, Stairs and Double Slab). See data values for the full list.

In a standard randomly generated Beta Map, you can find the blocks Air, Stone, Grass, Snow, Dirt, Water, Water Source, Lava, Lava Source, Sand, Sandstone, Gravel, Gold Ore, Iron Ore, Diamond Ore, Redstone Ore, Lapis Lazuli Ore, Clay Block, Coal Ore, Bedrock, Ice, Wood, Birch Wood, Pine/Spurce Wood, Leaves, Cactus, Sugar Cane, Pumpkins, yellow and red Flowers, brown and red Mushrooms, dead and living Shrubs and Tall Grass. In dungeons (added in Seecret Friday Update 2), you can also find Cobblestone, Moss Stone, a Mob Spawner, and Chests or a Large Chest, even though cobblestone and chests are usually made by the player. Obsidian can be found naturally, but it is not part of the random generation; instead it is created when naturally occurring lava source blocks and water come in contact. Cobblestone can also be found naturally, and is formed with the same circumstances as obsidian, except that it is formed when water and moving lava contact.

In the initial free version of Survival the player began with 10 TNT blocks and could obtain Dirt, Cobblestone from Stone, Wooden Planks from Wood, Gold Blocks from Gold Ore, Iron Blocks from Iron ore, Stone Slabs from Coal Ore, and white Wool  from Sheep.

In Classic mode the player can build with naturally occurring blocks, save Redstone and Diamond, and can use Bookcase, Sponge, Coloured Wool, Brick, Obsidian and Moss Stone. Operators of servers can also build Bedrock. Some custom servers give the ability to place Grass and (still) Fluids, too.

When playing the current Beta, the player can craft a variety of blocks not naturally found in maps, including Stairs, Workbenches, Paintings, Bookshelves, Furnaces and more. Redstone, Diamond, Gold and Lapis Lazuli can be found in the lower areas of maps, and Obsidian forms when water touches a spring lava block.

The blocks Netherrack, Glowstone, and Soul Sand can be found in The Nether, which the player can only enter by creating Portal blocks.