The slide is a technique which involves a finger moving along the string to its new note. The finger maintains pressure on the string, so that a continuous sound is produced until the desired note is reached. The left hand moves from one note to the next, upwards or downwards on the fretboard.
Only the first note is played by the right hand fingers, the second one is entirely produced by the left hand finger sliding up or down the fretboard. The length of the slide can be one or two frets or as many frets as you wish. Practice sliding individual fingers up and down the fretboard. Strike only the first note.
The slide is indicated on the music staff by a line leading up to the note you are sliding to. In tablature notation the slide is indicated by a line with the letter S above it.
Example 45 uses a semitone in an ascending slide whereas example 46 uses a descending slide.
Example 47 uses a tone in an ascending slide whereas example 48 uses a descending slide.
Practice sliding on any left hand fingers and on all strings.