Excuse me if this has been asked before, but what is the notation called when after the timing there is:
two quavers = one crotchet, one quaver, as a triplet
An example is on this music
This is swung eighths; more loosely, the music has "swing". More precisely, I'd refer to it as "triplet swung eighths" or "triplet feel" if the intent is more of a 2/3,1/3 breakdown. In blues influenced music, it might be referred to as a [blues] shuffle. In classical music it is referred to as notes inégales.
Jazz purists may balk at the term "swung" (or swing) since in that idiom, the term swing conveys a rhythmic feel that is distinct from whether the initial eighth is elongated (that's why it's indicated as being loose talk).