Plains

Plains are mild, grasslands biomes. They are among the first biomes added to the game. There are two plains biome variants in the biome family.

Description
Plains are mostly flat, with only limited, gradual changes in elevation. The surface is covered in grass and tall grass. Small and large oak trees rarely generate in the plains, and are the only source of wood in this biome apart from villages and pillager outposts. Some patches of plains can grow various colors of tulips, and these patches (along with flower forests) are the only places where tulips may generate. In addition to the tulips, oxeye daisies, cornflower and azure bluets may sporadically generate within the plains. Sunflowers can be found in the sunflower plains variant. Both types of plains, alongside with flower forests, are the only biomes where bees and bee nests can be found.

Villages that generate in plains biomes are made mostly of oak planks and logs, and other villages across the world default to this plains style if their meeting points are generated in unusual biomes, such as rivers. Horses can spawn in plains biomes, and (along with savanna biomes) is the only place where horses can spawn. In Bedrock Edition, this is only biome where donkeys can spawn.

Despite the calmness, survival in plains biomes can be a bit tricky due to the relative sparseness of the biome, though villages can serve as a temporary refuge if it is found. Oak trees sparsely generate, making wood scarce should one not want to tear down village houses for wood, however one can tear down pillager outpost towers. Additionally, the massive amounts of tall grass can prove to be a nuisance when building a shelter or when fighting hostile mobs. However, tamed horses can serve as a method of fast travel, allowing players to more efficiently explore their surroundings for more resources.

Variants
There are a total of two different plains biomes variants.

Plains
The Plains biome is the standard and most abundant plains variant. After forest, it is the second most common biome in Minecraft. There are also some unique features concerning the standard plains biome in the game's world generation: small forest biomes often generate in patches within large plains biomes, and small plains biomes generate in patches within large dark forest biomes as glades. It also generates as a separation when a swamp biome generates alongside a desert.

Villages and pillager outpost may generate in the plains biome, and horses and donkeys can spawn here.

Sunflower Plains
Typically found in large patches within regular plains, the Sunflower Plains variant features large numbers of sunflowers across its landscape, and is the only place where sunflowers may generate. The sunflowers make for a good source of yellow dye and a makeshift compass, as they always face east. The terrain is otherwise no different from the regular plains biome, and horses will still spawn here. Also villages and outposts still can generate here.

Trivia

 * The plains biome also generates in patches within dark forest and regular deep ocean biomes, similar to how 'Hills' biomes generate within their respective base biomes..
 * Plains use regular forest and forest hills as their hills biome variants.