A bass note run is a series of single notes, played on the bass strings, used to connect two chords. Bass note runs usually start on the *root note of the first chord and progress through the scale to the root note of the new chord.
A chord run features notes of the chord and/or scale, but does not progress to a new chord.
You should experiment as much as possible with bass note runs and chord runs. Their use will embellish your rhythm playing, particularly in folk, country and ballad styles.
The following exercise uses the chords in the key of G, together with examples of bass notes and chord runs.
*The root note of a chord is the note which has the same name as the chord, e.g., G is the root note of the G chord, C is the root note of the C chord and D is the root note the D7 chord.