Union affiliation by US state means how many workers in each US state belong to and are members of a union. A union is an organization made up of workers that come together to speak out for each other and make sure everyone has fair working conditions and workplaces. A union also tries to make sure workers get the salary and benefits they deserve, and there are laws in place that help protect union members. To join a union, a worker must be part of a certain industry or job and choose to be a part of the union. The number of union members in each US state tells us how many people in a particular state have decided to join a union. This number can be different from state to state, because of different job industries or laws in the state.