K as I was reading these replies the last one explained the artificial harmonic well. I think the other one I can try to patch up a bit better. The pinch harmonic is not actually pinching the string, just in case you are starting out and hear the term and think that pinching is involved. Pinch harmonics is basically hitting the string twice with one stroke of the hand. The first thing to mastering this technique is holding the pick properly. When soloing I like to try to hold the pick so that it jsut barely is larger than my thumb. This way when I want to do a controlled pinch harmonic I can just slightly tilt my hand towards the guitar body. Next is the stroke you need to take in order make this sound. When you hit the note, tyr to tilt your hand back a bit and then follow through. So you stroke and pick the note, first with the pick, and then, without trying to hard, hit it with the thumb bone part or any part which will graze the string. Do not consiously try to do the double touch through picking then touching, it is just a natural thing that needs to be played with and then one day you'll know exactly how to do it everytime. This is one of the most famous effects in guitar music. You can make a harmonic out of any note. To me the best sounding harmonics are pinch harmonics which are on the low e and a string.
Artificial harmonics are easier to do. When you strike a note, count 12 frets from that note and while the note is still ringing lightly touch and release above this twelfth fret. This move is not used as much as it is harder to do fast. Yet it is similiar to tapping the note and getting a harmonic. Eddy Van Halen did a solo in Buenos Aires which shows this technique very well. You should be able to find it on Kazaa or Morpheus. Watch it is might demonstrate this technique better.
Master this technique as it gives great style to a solo!!
Thanks, hopefully that helped and if I am wrong in terminology then just inform me so I don't spread ignorance.
Thanks again!