Which type of engine uses rotary motion instead of reciprocating motion?

A rotary engine is specifically designed to utilize rotary motion instead of the reciprocating motion characteristic of traditional piston engines. In a rotary engine, the combustion process drives a rotor that moves in a circular path within an oval-shaped housing. This design allows for a continuous and smooth rotation, generating power efficiently without the back-and-forth movement seen in reciprocating engines such as two-stroke, inline, or other types of piston-driven engines.

The design of a rotary engine enables a more compact form factor and often results in smoother operation and reduced vibration. Elements like the rotor shape and housing geometry are critical to its functioning, differentiating it from other engine types that rely on pistons moving up and down within cylinders. This unique mechanism is fundamental to how power is produced and utilized in rotary engines, making them distinct within the broader category of engine designs.