THE BLUES MAJOR PENTATONIC SCALE
The fourth mode of MAJOR PENTATONIC or fifth mode of MINOR PENTATONIC. I have also seen this called THE SCOTTISH PENTATONIC SCALE.
It contains the noted 1,2,4,5,6.
It'll fit nicely anywhere you'd use IONIAN, DORIAN or MIXOLYDIAN.
I've seen this called BLUES MAJOR PENTATONIC quite a few places which is odd since it doesn't have a 3rd so isn't really major or minor, but since it's probably used a lot over with MIXOLYDIAN or with MAJOR PENTATONIC or MAJOR BLUES SCALE I guess that makes sense. It's equally at home though anywhere you might use DORIAN.