Categories of fittings

Fittings can be grouped in one of the following categories:
Fittings that extend or terminate pipe runs
Couplings
Adapters
Caps and Plugs
Fittings that change a pipe's direction
Elbows (ells)
Fittings that Connect two or more pipes
Reducers
Bushings
Flex couplings
Fitting reducers
Adapters