There are many uses for a pentatonic scale and here is one of those uses. Of course you know that a pentatonic scale is composed of just 5 notes – the root, 2nd, 3rd, 5th and 6th of a major scale. In the key of C that would be C, D, E, G, and A. In the key of Eb it would be Eb, F, G, Bb and C. In the key of Gb you would simply use all the black keys – Gb, Ab, Bb, Db, and Eb.

Watch this short video to get an idea of one thing you can do with it:

If you are interested in learning to improvise, be sure to check out this great resource: http://www.playpianocatalog.com/piano-improvising.html