Greedy best-first vs. A* search
•Greedy best first expands the node that gives the least estimated cost to the goal: f(n) = h(n).  It ignores the step cost entirely. •A* combines uniform cost search and greedy best first search f(n) = g(n) + h(n).
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Figure 4.2 (pg. 96) shows GREEDY-BEST-FIRST-SEARCH finding a solution without backtracking.
To think about: is this always the case?
Also: Can you come up with search trees in which GREEDY-BEST-FIRST-SEARCH would be better suited than UNIFORM-COST-SEARCH?  How about the other way around?

Note that in all cases that the appearance of a goal state in the fringe does not mean that the search will terminate right away and choose to expand that state.  To think about: can you make any general statements that quantify the time in which a goal state appears on the fringe and when the search algorithm terminates with a goal?