Here's a cool technique that can enable beginners to play super fast lead guitar. This was popularised by Eddie Van Halen back in the 80s, but it can be traced right back to the 40s.
This is only really recommended for electric guitarists, and is easier with some overdrive or distortion on your sound, even from your amp or a pedal.
Acoustic guitarists should check out the video at the bottom of this page for inspiration!
Does this work on acoustic? Yes.. but it's much harder to get the notes ringing out. Check out this video below - Playing starts from about 1 minute in!