A heated bed is a component used in 3D printing that helps improve the adhesion of printed materials to the build surface. By maintaining a consistent temperature, it reduces the risk of warping and ensures that the first layers of the print stick properly, leading to better overall print quality. Heated beds are commonly found in FDM printers and can be made from various materials, such as glass or aluminum, often coated with a material like PEI or Kapton tape to enhance adhesion. Users can typically adjust the temperature settings based on the type of filament being used, such as PLA or ABS.