Being a social wasp, yellow jackets are capable of producing a painful sting, but none leave the stinger embedded in the skin, allowing them to sting multiple times. Most stings occur when the colony is disturbed. Wasps are very protective of their colony and will attack if someone approaches within a few feet of the nest.  The western yellow jacket is found around natural areas with in-ground nests, while the German yellow jacket typically makes nests off the ground and is often found in urban areas. 
Common worldwide, and particularly abundant in the southeastern United States, yellow jackets are carnivorous, primarily feeding on other insects like flies and bees. They also feed on picnic fare, fruits, carrion, and the nectar of flowers. They will forage for about 1 mile from their nest.
Yellow jackets are not friendly. Unlike their friendly counterpart and local pollinator the bee, they can be ruthless when disturbed. Due to the hazard of severe reactions to stings, it is recommended to hire a professional to eliminate its nest.
They often build their nests underground or in hollow logs, tree stumps, attics, between walls, under eaves and inside recycling bins where sugars are common.  If you see signs of yellow jackets in or around your home, it’s best to take the necessary precautions to get rid of them. In the event that you have enough distance from the nest to not fear an immediate threat, bait traps are an excellent way to lure them away from locations with human interaction. Bait traps that use a sugar or protein-based food lure will appeal to the widest range of social wasps. Due to their diet, these baits will effectively lure and trap those that pose a risk.
The German yellow jacket has a proclivity to nest in attics or in the walls of buildings. This proximity to people makes this species of yellowjackets more of a public health threat. Because it nests in protected places, temperature alone does not limit this species, allowing for a few active nests of this species to survive all year long.
These are the wasps which harass people at outdoor eateries, theme parks, receptions and picnics, congregate at bakeries or candy factories, and they actively seek out spilled sodas at sporting stadiums, etc. 
Approximately 1in in length (Queens can grow up to 1.25in)
Dots along the abdomen with 3 dots on the face
About 4,000 wasps live in each nest, measuring about 2ft in diameter