MDF, also known as medium-density fiberboard, is a composite made from wood fibers and glue. These components are heated, pressed together and covered with a veneer. Using MDF is a less expensive option than using real wood, however, MDF is less durable and tends to split easily.
MDF does not contain the grain or knots found in solid wood, though the appearance of solid wood can be obtained with the use of a veneer. It is a poor choice for areas exposed to excessive moisture because
water makes MDF swell. The inner surface of MDF is easily crushed and should be protected from accidental damage during installation.