The Pacific Ring of Fire is not a boundary type itself, but rather a zone of intense geological activity. It's characterized by a chain of volcanoes and frequent earthquakes along the edges of the Pacific Ocean. This activity arises from the interaction of multiple tectonic plate boundaries:

* Convergent boundaries: Where plates collide. This is the dominant type of boundary within the Ring of Fire. These collisions can cause subduction zones, where one plate slides beneath another, leading to volcanic eruptions and earthquakes.

* Transform boundaries: Where plates slide past each other horizontally, causing earthquakes.

The Ring of Fire encompasses both subduction zones and transform fault lines, making it a region of extreme geological activity.