The slide is a technique which involves a finger moving between two notes on the same string. 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. The slide is indicated by a line joining two notes. Only the first note is played by the right hand; 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 fret or as many frets as you wish.
Practice sliding your finger up and down the fretboard. Pick 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.
Here is an example which uses slurs and slides. Each technique is indicated in the notation. Notice the use of sixteenth notes in this example.
Here is another example using hammer-ons. This one is played further up the neck and contains two notes hammered together. Take it slowly until you can play it comfortably, then gradually speed it up.
Here’s a final example which uses hammer-ons and slides. As with previous examples, take it slowly at first until you can play it easily, then gradually increase the tempo. Keep playing, keep practicing and have fun.