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What is a flop (and when are they conjectured to give derived equivalences)?

(1) Is the definition of flop given by Wikipedia the industry standard?

(2) Regardless of the answer to (1), when is it expected that a birational transformation gives rise to a derived equivalence?

The reason I'm asking: apparently it is conjectured that different crepant resolutions are derived equivalent. On page 40 of this paper of Bondal-Orlov, they conjecture that flops induce derived equivalences. Apparently "flop" is sometimes used to mean birational transformation preserving canonical classes (without specifying the type of surgery actually being performed). So I'm interested to know whether such transformations are expected to be factorizable into (Wikipedia) flops, or produce derived equivalences for other reasons.

GS