The term biome is analogous to its scientific usage: on Earth, a biome is climatically and geographically defined by distinctive communities of plants, animals and soil organisms supported by similar climatic conditions. They are often referred to as ecosystems.
The plains biome was the first released biome in Minecraft, and so covered the entire land. It consisted of mainly Grass,and Dirt. The map had no end. Trees were added later in the game, then the release of Ore Blocks, (like redstone ore). Plains are the most basic of all lands, yet one of the hardest to live in, due to the lack of trees. If you have already cut down all of the trees in the area that you have started living in, you would have to go long distances to find more, unless you give to server command or plant a sapling you get from the leaves of the tree. Another disadvantage of plains is the tall grass, which may obscure spiders and baby zombies.
VillagesVillages (also known as NPC Village) are small "living spaces" that were added in the Adventure Update (Beta 1.8), being naturally placed on any World Seed. They are the homes of Villagers.
In the Beta 1.9 Pre-release (never official), Villager mobs, also known as Testificates or NPCs, were added to spawn in Villages. Villages can also be used for the player's house. If Village structures are taken apart they offer the following items: wood, wood planks, pressure plates, fences, cobblestone, wheat stalks, gravel, wooden stairs, and other items. Some Villages spawn in the deserts, and they have sand, sandstone, and sandstone stairs. It is somewhat rare to find a village in the plains. some villages have particular items that can be found in most villages, but not all. these items include: bookshelves, lava, potatoes, carrots, iron, and furnaces.
The desert biome is one of the only places you can find cactus, the others being a beach and Mesa. there are hills and small mountains made of sand and sandstone. In the desert you can also find desert wells. Desert temples also spawn in deserts with treasure and a trap to kill you. The temples will only spawn on flat areas of the desert and will break world generation if it spawns on a hill.
Tundra biomes, known as Ice Plains in-game, are biomes completely covered in snow and have ice blocks due to water freezing (breaking ice produces water). Spruce trees are found in this biome. There may be packed ice spikes. Wolves also spawn here. If it rains in other biomes, it will snow in this biome.
Swamp Biomes feature small shallow bodies of water and dull-looking grass, presenting oak trees covered in vines. There are plenty of oak trees, though not as many as forests. Slimes and Witch Huts can be found in swamps. Lily pads can generate in water, so swamp biomes are the only natrual source for lily pads.
In Minecraft: Pocket Edition, Giant Mushrooms spawn in this biome starting in the upcoming 0.10.0 update.
Jungle Biomes are very forested biomes. They have the biggest trees out of any biome. They also have these unique traits. They are the only biome where ocelots spawn. They also have Jungle Temples. Jungles look more like a Tropical Rainforest. Coco bean pods spawn here, and as of 1.7.2, melons can be found "wild" here. Melons have also been made much more common.
Redwood ForestThe Redwood Forest Biome, also known as Mega-Taiga or Mega Spruce Taiga contains various blocks including Podzol and a varient of Dirt. Also featured are 2x2 Spruce Trees along with Ferns, Mushrooms, and Dead Bushes. This biome also features boulders made of Moss Stone that serve as a decorated purpose.
The Mesa Biome features various colors of clay that can be mined and dyed for decorated purposes. Also found in this biome, is red sand, which was implemented in 1.7. The only other things included in this biome are Dead Bushes and Cacti. Mesa biomes are very rare, and usually spawn near Savannah biomes.
Ocean Biomes are extremely large open biomes made of water. Far beneath the water is a landscape made of gravel, dirt, and clay. Ocean biomes often flood into Abandoned Mine Shafts or caves. Occasionally, oceans have small two block wide air patches. Ocean biomes have no maximum size but usually are found between 10,000 and 25,000 blocks wide. Occasionally, in Ocean biomes, you can find small islands with little vegetation. Players can spawn in Ocean biomes on an island with no wood in the middle of nowhere forcing them to cheat, make a new world, or swim to find land.
Deep ocean biomes are a variant of ocean biomes, they are much deeper than regular ocean biomes. The ocean floor consists of gravel. They can be 30 blocks deep, making going under one dangerous. However, you may see some light underwater, that light comes from an Abandoned Mine Shaft.
Extreme HillsA highly mountainous biome with dull grey-blue grass and a few scattered oak trees. Cliffs, peaks, valleys, waterfalls, overhangs, lavafalls (though not very likely), and many other structures exist, creating outstanding views. More underground cave systems are present here than in any other biome. Falling is a significant risk, as there are many ledges and sudden drops, often not visible, and the drops can be large enough to cause severe fall damage or even death. Extreme Hills (and Extreme Hills Edge) are the only biomes where Emerald Ores spawn. As of 1.7, Spruce Trees spawn here as well. if the mountain gets high enough, snow could cover the mountains.
A biome with spruce trees and dull grey-blue grass. Snowfall also occurs in this biome, forming snow and ice. Hills are common, and wolves are found in this biome more frequently than in others. Spruce Trees are this biome's tree. Water will freeze in this biome, into ice. Sugar can can spawn here but it'll break down due to the freezing of the ice.
The roofed forest biome was added as of 1.7.2. It features dark oak trees and huge mushrooms. The roofed forest biome is a very dangerous biome to spawn in as there are many dark places in the forest where hostile mobs are likely to spawn. But yet it's also the more common biome for huge mushrooms instead of searching for a mushroom island, which are very, very rare.
SavannaThis biome features dull, dry grass, and acacia trees. NPC villages spawn naturally here, along with horses. It never rains in this biome, often connected with deserts or mesas (if you create a new world using the seed "Indev", you will spawn next to a Savanna biome with a Desert biome connecting to it).
This biome only includes Birch Trees, with some Oak Trees possible. It also looks much like a forest biome although none of the birch trees can be large like their oak variants. But if its a hilly version of this biome, the birch trees can be extra tall.
Main Article: The Nether
This biome is the Nether dimension. It is the first dimension that was released with the game. This biome features more mobs and a new structure, the Nether Fortress. The only way to get to The Nether biome is to build the portal made out of Obsidian. It also reqiures Flint and Steel.
Main Article: The End
This biome is the End dimension. It is the second dimension that was added in an update. The biome features lots of Endermen and a boss to defeat, the Ender Dragon. There are also lots of Ender Pillars with healing crystals to prevent the Ender Dragon from being killed. To get to The End biome, you need to find a stronghold first, because you need to find an End Portal to get to The End. There will be 14 Ender Frame Portals, you need to insert all 14 of your Eyes of Ender in order for the portal to work. Once this is done it will open and you can go in the End.