What is the difference between a divergent and convergent plate boundary?

A divergent (constructive) plate boundary is one where the two plates are moving APART from each other in opposite directions. As these plates move apart they create cracks in the earth's surface which allows magma from the mantle to fill the gap. This enables new features such as volacnoes and mountain ridges to develop.  A convergent (destructive) plate boundary is one where the two plates are moving TOWARDS each other. The oceanic crust is subducted beneath the continental crust causing earthquakes and fold mountains to form from the subduction zone.