Catalytic stoves use a ceramic combustor coated in a catalyst to reburn smoke at lower temperatures, giving you longer, steadier heat output and better fuel efficiency. The trade-off is a bit more upkeep — the combustor typically needs replacing every few burning seasons. Non-catalytic stoves rely on a baffle system and pre-heated secondary air to burn off smoke instead. They're simpler to operate and maintain, though burn times are usually a little shorter and efficiency slightly lower than a well-maintained catalytic unit.