Other than 12-bar blues, the most common chord progression in jazz is known as a ii-V-I (or more commonly, a ii7-V7-I7).
Sometimes, sequences of ii-V-I progressions are used.
Another technique that is sometimes used in a ii-V-I progression is called a tritone substitution. In a V7 chord, the third and seventh are a tritone apart. A tritone substitution is when the V7 chord is replaced with the other dominant chord whose third and seventh form the exact same tritone.
When improvising, jazz musicians select notes and scales that match the chords being played by the ensemble. This is called “playing the changes.” Since the backgrounds are usually dominant seven chords, major scales will often clash with the notes of the chord. Jazz musicians respond by using modes in their improvisation. What mode of the scale has been used here?
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