Medium-density fiberboard (MDF) is a sawdust/wood particle and glue composite fused with heat and pressure to make a simple sturdy material.
MDF can look very uniform but varies quite a bit in qualities from the cheapest to the more expensive varieties. It is noted for being dimensionally stable, but having poor resistance to water although moisture-resistant versions (MR-MDF in some markets) are manufactured and there are even some versions that can be used externally. Moisture-resistant versions tend to be coloured to make them easy to distinguish from the normal kind.
