Different kinds of joints.

Gliding joint.
this kind of joint allows the bones to glide past past each other in ether direction along the plane.

Hinge joint.
this joint is mainly found in the ankle, elbow and knee joints, these joints can only flex and extend.

Saddle joint.
this is the joint in witch one of the joints is shaped like a saddle, and the other bone rest on it like a rider on a sadde, they are ultimately more flexable than the hinge and glide joints.

Ball and socket joint.
this joint is primarily found in the hip and is a shaped like a sphere and a socket which the sphere lies in, this joint allows rotation and multidirectional movement.