Being a new(er) bike mechanic, found a really good pic for differences in bottom brackets, as I could not find solid references with pics on here.
Was replacing my TruVativ power spline 68x113 BB, and was mistakenly told an Octalink v2 would work as a replacement. That was not the case.
Anyways, thought this pic might help other newer mechanics who are learning the trade as they go.
In pic: from left to right is: Square Taper, Octalink v1, Octalink v2, ISIS (or TruVativ calls it Power spline).