There is chip board which is rough and usually covered in a wood veneer or plastic or there is MDF (Medium Density Fibreboard) which is a lot smoother so does not need to be covered in anything. There is also ply-wood where thin slices of wood are glued together or, less common these days, block board in which uniform sized pieces of wood are glued together and sandwiched between smooth wooden facings.
Avoid breathing in dust from MDF as it can cause irritation.
If it looks like this, it's chipboard:
http://imagewa.com/PhotoPreview/380/380_...
Could be MDF (medium density fibreboard) but you probably mean chipboard.
MDF
There is a material that looks like little pieces of wood compounded together. It can be used to make tables and shelves. What is that called?
