Although it is possible to make a good sound picking every note, it is more common to use a variety of left hand techniques to add expression to some of the notes. These techniques are essential in all styles of guitar playing and should definitely be mastered. Be sure to play right on the tips of the fingers when practicing these techniques.
When two notes or more are played in succession and only the first note is picked, the notes played by the left hand only are said to be "slurred". A slur is a way of connecting notes more smoothly than when articulating every note with the right hand. A slur is indicated by a curved line above or below two or more different notes.