well I am assuming thisis really obvious to you, but maybe not...
BSP = 2
quadtree = 4
octree = 8
BSP trees split the world over plane boundaries into two subsections, which then get further divided, etc...
wheres quadtree split the world into quarters, which are each them subdivided into questers, etc... generally omitting the verticle dimention for things like maps. Finally octress split into 8 (quad tree divided in 3 space)
One other characteristic is that BSP trees require you to actually cut ploygons, so one polygon cannot span multiple nodes of the tree. This is not the case in a QT or OT, one polygone can cross into any number of subdivisions.
Another thing is a QT will generally store 4 floats, OT will store 6, and im not sure about BSP, but I think they store the plane, so 4. (
the basic point being that if you get a 2 branch tree: bsp, 4 branches: quad: 8 branches octree.
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