Man Made Wood

As explained, man made 'wood' is a material constructed from the by-products of timber. As real timber is becoming more scarce (and therefore more expensive), it is neccessary and useful to produce artificial timber, which is relatively cheap, and sufficient for the job. Below are a list of the most common types of man made woods.

Plywood

In woodworking, it is often difficult to find a durable timber that weighs very little. Plywood is such a product, and could almost be alluded as 'the titainium of (man made) woods.' Thin sheets of wood are glued together so that each grain is perpendicular to the last. Thickness ranges from as little as 3 sheet ply, all the way to (inch thick) 5 multiply.
Picture
(Source: http://hardwoodplywood.win.mofcom.gov.cn/www/9/hardwoodplywood/img/2009324124720.jpg)
Chipboard

Timber chips and pulp are mixed with resin and tightly compressed to form chipboard. Although extremely affordable, chipboard has relatively few uses in proper woodworking, mainly because of its weak and unstable nature. Disadvantages are that it swells with moisture (making it unsuitable for outdoor projects), and damages the blade of cutting tools. Veneered chipboard is also an option, which makes the surface more asthetically pleasing.
Picture
(Source:http://img.alibaba.com/photo/11196426/Melamine_Chipboard_Particle_Board_.jpg)
Medium - Density Fibreboard (MDF)

Not unlike chipboard, MDF is made through the compression of timber fibers, and is a good, cheap wood for experimental projects.
Picture
(Source: http://aavaas.com/wp-content/uploads/mdf.jpg)
Blockboard

Slightly unstable, blockboard are comprised of strips of pine or oak bonded together. This wood can easily be used in home projects, because of how well blockboard resembles natural wood.
Picture
(Source: http://pirun.ku.ac.th/~b4803116/Block%20Board1.jpg)