What are the types of couplings?

Couplings are mechanical devices used to connect two shafts together for the purpose of transmitting power. There are several types of couplings, including rigid couplings, which provide a solid connection with no flexibility; flexible couplings, which can accommodate misalignment; and fluid couplings, which use fluid to transmit torque smoothly. Each type serves different purposes, such as accommodating shaft misalignment, damping vibrations, or allowing for some degree of movement between connected parts.