Watch the Lesson 11 online guitar lesson by David Hamburger from Fingerstyle Blues Handbook 1

G7/B is pronounced "G7 over B," and it means - you've got a G7 chord played "over" a B bass note "over" because the B note, as the lowest note in the chord, is on the bottom. We've just moved the open second string B note from an ordinary G7 chord voicing down an octave, to the second fret on the fifth string, and doubled the open fourth string D note from an ordinary G7 at the third fret of the second string.