The Wasp is a small, hostile arthropod mob. The wasp has very little health and does minor damage, but can be hard to hit due to its small hitbox and aerial agility. Wasps normally won't bother the player unless they come within 10 blocks of eachother, and don't drop anything, so running away from them may be best practice. Wasps will attack bees.
When not attacking players or bees, wasps will fly around aimlessly, around 1-4 blocks above the ground. During the daytime, wasps avoid darkness, and during the night or a rainy day, they rest on the ground and won't notice a player unless they are within 2 blocks of the wasp.
Wasps occasionally build nests, which they prefer to build in sheltered areas protecting them from rain; Such overhangs can include player homes. A wasp nest will spawn a new wasp every 4 minutes or so, but wasps do not build nests within 140 blocks of eachother, so they will not multiply exponentially. Wasp nests can be broken by hand or shot down with a bow, but in either case, 2 angry wasps will spawn, and all the wasps in the region, enraged with the destruction of their colony, will boost their detection radius to 30 blocks.
Wasps only spawn amongst tall grass and flowers in birch forests (including Birch Forest Hills, Tall Birch Forest, and Tall Birch Forest Hills), flower forests, and swamp hills, and will take damage if they go into any biome colder than 0.5 (the temperature of a river) or are caught in snowy weather, eventually dying if they do not return to a warm biome; Wasps will be protected from cold damage if they are within 2 blocks of a bright enough light source, but their AI will not actively guide them to huddle near the light.