Fiberboard is known as low density fiberboard is a type of engineered wood

Engineered wood

Engineered wood, also called composite wood, man-made wood, or manufactured board; includes a range of derivative wood products which are manufactured by binding the strands, particles, fibers, or veneers of wood, together with adhesives, to form composite materials...

 product that is made out of wood fibers. Types of fiberboard (in order of increasing density) include particle board

Particle board

Particle board, or particleboard , is an engineered wood product manufactured from wood particles, such as wood chips, sawmill shavings, or even saw dust, and a synthetic resin or other suitable binder, which is pressed and extruded...

, medium-density fiberboard, and hardboard

Hardboard

Hardboard, also called high-density fiberboard , not to be confused with 'hardwood', is a type of fiberboard, which is an engineered wood product....

. Fiberboard is sometimes used as a synonym for particle board, but particle board usually refers to low-density fiberboard. Plywood

Plywood

Plywood is a type of manufactured timber made from thin sheets of wood veneer. It is one of the most widely used wood products. It is flexible, inexpensive, workable, re-usable, and can usually be locally manufactured...

 is not a type of fiberboard, as it is made of thin sheets of wood, not wood fibers or particles.