What are the functions of thruster?

What exactly are the key functions of thrusters in the realm of aerospace and marine engineering? Are they solely responsible for propulsion, or do they serve additional purposes such as stability control and maneuverability? How do they operate, and what are the technical specifications that distinguish one type of thruster from another? Additionally, are there any limitations or challenges associated with their use that engineers need to be aware of when designing and operating spacecraft or ships?