A fireplace insert is a type of heating appliance designed to fit into an existing fireplace. It typically consists of a firebox, a flue, and a glass door, allowing for more efficient heating and reduced smoke emissions. Inserts can be powered by various fuel sources, including wood, gas, or pellets, making them versatile options for homeowners. These inserts help improve energy efficiency by directing heat into the room rather than allowing it to escape up the chimney. They also enhance the aesthetic appeal of a fireplace, providing a modern look while maintaining the traditional charm of a fireplace.