Basic labor terms: - Closed shop - must be member of union to be hired. - Union shop - must join union when hired. - Agency shop - don't have to join union,

Basic labor terms: - Closed shop - must be member of union to be hired. - Union shop - must join union when hired. - Agency shop - don't have to join union, but have to pay a fee to it. - Open shop - don't have to join union, but can. - Yellow-dog contract - not allowed to join union.[1] The two extremes are mostly illegal in the US. [1] https://en.wikipedia.org/wiki/Yellow-dog_contract https://en.wikipedia.org/wiki/Yellow-dog_contract