The first boundary is called divergent. 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 and this is a compression, or a stress that can shorten or compresses the plates.
Convergent boundaries cause mountain ranges to develop.
The Himalayas for example, were formed when the plate carrying India collided with the plate carrying Eurasia. This continental collision is still active and moving at a rate of 3 to 4 inches per year as the India plate is pushed under the Asian plate and the mountain continue to grow. Strong earthquake activity is very common with areas of convergent boundaries as well. The third type of boundary is a transform boundary and this is when the plates slide past each other along faults causing mid-oceanic ridges and trenches. One plate may be forced down into the mantle under the other plate.