Improvising Jazz
There are many different schools of thought on how to teach or learn jazz improvisation. Some people recommend learning all the relevant scales and how they fit chord sequences, some recommend learning lots of established phrases, licks and patterns, some recommend just learning and playing tunes by ear. The best jazz improvisers often can’t explain the process, it is something totally intangible: a combination of intuition, imagination and great ears. There are some improvisers who know relatively little theory but have the rare gift of hearing the chord changes and automatically knowing what to play. For the majority the best results come from a combination of hard study (private and tutored), lots of focussed practice, regular playing with other people and listening to the greats.
This section of the jazz pages became part of the Jazz Techniques Course at the University of Southampton. Learning tpo improvise jazz over chord changes can be quite intimidating at first. I recommend that once you understand some of the very basic theory it is a good idea to practice playing some simple modal patterns, as in the Dorian Patterns section. At all times bear in mind that although it is important to know the scales, you should be striving towards melodic playing, that the scales and modes are just a means to an end. After a while you should be able to combine the simple modal two-chord sequences with other chords so that you can improvise over more interesting progressions.