Cheap furniture is often made out of this, which is essentially a block of compressed sawdust held together with glue, often covered with faux-wood-grain contact paper for that extra touch of tackiness.

Dr. Demento once featured a song about it, to the tune of Particle Man:

Particle board, particle board
everything's made with particle board
twice the weight, half the strength
Particle board.

Particle Board has only one virtue, that is, price. It is cheaper than solid wood.

BUT: nails will not hold well in it. If you saw it, it tends to chip. Not all wood screws will work.
The greatest enemy of particle board is water: even small amounts of water will make to board swell and warp, destroying it for ever.