What are the major types of tectonic plate boundaries?

Answer 1

The major types of plate tectonic boundaries are:

Divergent Plate Boundary: The area where two plates are moving in relatively opposite directions and new crustal material is being created. Examples would be the mid-ocean ridges, and the East African Rift.

Convergent Plate Boundary: The area where two tectonic plates are moving toward each other and one of two things happens; either the more dense plate subducts under the lighter plate and heads toward the mantle, or, if the plates are of similar density, they cause uplift and mountain forming events. Examples would be the oceanic to continental crustal collision creating the Andes Mountains, and the continental to continental crustal collision creating the Himalayan Mountains.

Transform Plate Boundary: The area where two plates are grinding past each other, snapping into place from elastic rebound as they go, causing numerous earthquakes. The San Andreas Fault is an example of a transform plate boundary between the North American and Pacific plates.
Convergent (plates are crashing together), divergent (plates are spreading apart), and transverse (plates are grinding past each other.) There are key structures that you get at each: Convergent boundaries can produce subduction or uplift, resulting in mountains and volcanoes. Divergent boundaries form mid-oceanic ridges and rift valleys. Transverse boundaries create faults, and are prone to earthquakes.
They are all boundaries between or fractures within the Tectonic Plates forming the Earth's crust.

A convergent boundary is that between two approaching plates; usually an ocean-floor plate being subducted beneath the continental plate as the ocean closes. This is happening now to the Pacific Ocean.

A divergent boundary is the opposite: the fracture of plate into two parts moving away from each other. The break is closed by upwelling magma. E.g. The Mid-Atlantic Ridge - the Atlantic is presently widening away from this subsea mountain-range at a mean rate of about 25mm/yr.

Transform boundaries, or Transform Faults, are shear fractures across the plate at roughly right-angles to the spreading-ridge from which the emanate. They represent the effect of unequal spreading forces. If you look at a relief map of the Atlantic Ocean bed you will see many transform faults to E and W of the Mid-Atlantic Ridge

Answer 2

The major types of tectonic plate boundaries are divergent boundaries, where plates move apart; convergent boundaries, where plates collide; and transform boundaries, where plates slide past each other horizontally. Subduction zones, where one plate is forced beneath another, are a common feature at convergent boundaries.