The earth is divided into plates as proposed in the plate tectonic model. Each type moves in a different way, creating unique landforms on earth.
1. Convergent Plates 
Convergent plates are boundaries in which two plates are moving towards each other. There are three types of convergent plates.
A. Oceanic-Oceanic
In this type of convergent plate boundary, the oldest plate (the denser material) will be subducted into the mantle, creating island arcs and trenches.
B. Oceanic-Continental
Here, oceanic plates will be subducted producing volcanos to form on the continent.
C. Continental-Continental
In this type of convergent boundaries neither material will be subducted. Instead, the plates will fold and thrust, producing landforms such as mountains.
2. Divergent Plates 
Divergent plates are plates that move away from each other. Divergent plates are common in oceanic ridges or "spreading centers." What happens here is that as the plates spread apart, the pressure in the mantle is reduced creating what is called pressure release melting. Divergent plates are also the cause of contintal rifts. This is when pre-existing continents spead the continent apart when two divergent plates move. An example of this would be South Africa.
3. Transform Plates 
Transform plates are boundaries that slide horizontally pass eachother in opposite directions producing ocean ridges. An example would be New Zealand.
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Types of Plate Boundaries
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