A Divergent plate boundary is when two plates are moving away from each other, which allows molten rock to rise up from the mantle to the surface and cools forming new crust.

A Convergent plate boundary occurs when two plates meet each other. One of two things will happen when the plates meet, either they will both push up against each other forming mountain ranges, or one of the plates will bend down.

A Transform plate boundary happens when one plate slides laterally past another. During this plate movement, no new crust is created nor destroyed. This will typically lead to canyons or fault valleys and is a common cause for earthquakes.

Seafloor spreading typically occurs at Divergent plate boundaries. The two plates pulling apart creates a mid-ocean ridge, which is kind of like an underwater mountain range. During this process, the scalding magma rises to the surface only to be promptly cooled by the frigid water, creating a new seafloor.

As the Oceanic plates come together at a Convergent boundary, typically the older plate will be the one to subduct and will eventually melt and be recycled into the Asthenosphere. The two plates converging creates an Oceanic trench, and the rising magma from the subduction of the older plate can lead to Volcanos.

Most oceanic transform faults will connect segments of Diverging or Converging plates. These transform boundaries typically countervail the active spreading ridge and are typically found on the ocean floor.