在分支和绑定和最佳优先搜索之间的差异。

I am studying branch and bound and best-first search for my thesis work but found lots of contradictions on the web about these two concept. First I thought branch and bound only prune the branches ending to high cost solution (using heuristic) and do not prioritize the search (do a simple DFS or BFS on the rest of a tree after the pruning). However, later I found many resources that say BB ranks the states as well and considers nodes with higher rank first (a prioritized search). If it is so, what is exactly the difference between BB and best-first search?I am studying branch and bound and best-first s