Some licks are made easier to play by barring the 1st finger across two or more strings while the other fingers play additional notes.
In the licks below the 1 st finger of the left hand bars across two strings (i.e. holds down two notes together) while the 2nd or 3rd finger plays hammer-ons. This baiTing technique increases the speed of your playing.
In the licks below the G and D strings are barred by the 1st finger at the 5th fret.