This is a tension or a stress that pulls the plates apart. Divergent boundaries cause mid oceanic ridges. Some other common characteristics are high heat flow, mild volcanic activity, and shallow earthquakes. The second boundary is called convergent. This is compression, or stress that can shorten or compress the plates.
Convergent boundaries cause mountain ranges to develop.
The Himalayas were formed when the plate carrying India collided with the plate carrying Eurasia. Strong earthquakes are very common with convergent boundaries as well. The third type of boundary is a transform boundary. This is when the plates slide past each other along faults. One plate may be forced down into the mantle under the other plate.