Broken Bones.

The types of fracture you can get include:

A comminuted fracture is when a bone is broken into two pieces. At the very least, three separate parts of the bone must be broken in order for this to be considered a comminuted fracture.
A greenstick fracture includes an incomplete fracture where one side of the bone breaks and the other side bends
Transverse is when the fracture is perpendicular to the axis of the bone
The compound fracture has to do with the bone ending and penetrates the skin
Spiral fracture is a ragged break and the bone is excessively twisted, common with sport injuries.

Epiphyseal fracture is when the epiphysis separates from diaphysis along epiphyseal line and it occurs where cartilage cells are dying.

Compression fracture is when the whole bone is crushed as you can see above.

The depressed fracture looks like the worst to me but it occurs when a broken bone portion is pressed forward. This is the typical skull fracture.

The nondisplaced fracture above shows that the bone ends assume the same position. 

Displaced fracture is when the bone is out of complete alignment.

The complete fracture has to do with the whole bone being broken all the way through.