The Pentatonic Scale is one of the more useful scales in music. We love to use this scale when improvising and soloing, because all the notes tend to sound real good in most situations. The pentatonic scale only has 5 different notes (penta=5) so the sometimes harsh and clashing notes have been removed.
On the guitar, the pentatonic scale can be broken down into 5 basic shapes. Each shape connects with the one before and after it. If you where to start the patter below on the first fret of the 6th string, you would be forming all the pentatonic shapes for the key of F minor.