× = don't play that string, ○ = open string. Numbers next to a diagram give the fret it starts on.
See every E♭m note on the neckE♭m is one of the seven chords in: B major (iii), G♯ minor (v), F♯ major (vi), D♯ minor (i), D♭ major (ii), B♭ minor (iv).