People often pose the question "what makes metal... metal?" Well, firstly, for posing such a vague question you deserve to be shot! But I'll try my damnedest to make the point...

Metal guitar playing comprises of many features, techniques, tricks, or whatever you want to call them. You'll often find that guitarists will form their own little niche where they excel in one particular area, no different from a footballer's flare or a chess player's technique, and eventually it becomes part of their signature sound. However, the idea is to be a well-rounded player before you find your niche.

Heavy Metal Guitar Lessons

By all means shred, but you'll find the timing so much easier if you have a tight discipline in rhythm. You don't run before you can walk, in other words. I also feel nowadays that a lot of flare has been taken out of guitar riffs, and they're used purely as a stepping stone to get to the next shred passage, or a random section of sweep picked arpeggios are thrown in for good measure. A riff is the main body of the song, it's the bit you remember, and it's the music! If it's not grabbing people's attention, it's not catchy, it has no 'hook' and it's just generic, then you need to revise what the riff is all about!

I've noticed nowadays that some people make the mistake of jumping ahead, and go straight onto trying to shred as fast as they can, locking themselves away in their bedroom practicing scales to a metronome, but they don't have a creative bone in their body, and if you asked them to write something they'd be stuck! Not to mention their technique tends to be under par, because they don't have the foundation to build on. Solid rhythmic techniques are the foundation of any guitar great. Without it you have no sense of feel and groove, and it's imperative if you don't want your playing to be mechanical and lifeless!