Slipin advice is spot on. I really really wish I had realized this years ago. I think my skill level would be much higher if I did.

I used to practice with no metronome and not even plugged into my amp. I would get the notes and patterns down, but I was doing it in a vacuum. If I went to the song to play over it, I would often find I was practicing it too slow or sometimes too fast!

Simply putting a drum beat behind scale pracitices makes it musical - it's an amazing thing. Practicing over a drum beat also forces you to get your timing down, especially if you are practicing a song. If you timing is off, it becomes glaringly obvious! It makes it so much more fun because you feel like you are playing over a band even though it is only a drum. The advantage of playing over a drum beat as opposed to a backing track is you are free to play in whatever key you want - it's wide open. You can also move from song to song and it sounds like you are putting together a medly. Playing over a backing track is important too because that forces you into a musical context, but don't underestimate the power of just a drum track.

Just like a metronome, you can change the tempo so it allows you to practice passages or scales at a comfortable tempo.

Another skill you develop practicing this way is *listening* to what is happening as you are playing. Listening and timing are two skills that are really important but are often overlooked. Simply using backing tracks and drum tracks to practice over incorporates learning of these skills into everything you do.

...and that's not all! Something else you can do is combine the functionality of a drum beat and a backing track in something called a looper. My Zoom G5 pedal has this capability. You call up a drum beat, record a riff, chord progression, whatever over it and loop it. You are now free to jam over your creation unti the cows come home. Something like that might be more appropriate once you've developed you playing skills a little more, but it's something to think about. Look on you tube for "guitar looper" or "g5 loops" and you'll be amazed at what people can do with it.

I probably sound like an advertisement for a drum machine/amp company, that's not my intent. Practicing this way just completely transfomed my enjoyment and effectiveness of my practice sessions in a way I could never have imagined.

So, (in short :-), if you can get an amp that offers some of this, it will significantly help you develop your playing skills.