"Speaker Types
Let us start with component, a component setup usually consists of crossovers, a tweeter, and a woofer. This makes for the best you can get. The reason for this is because of the first component. The crossover, before that power even gets to your speakers the crossover filters the frequency's of the music and makes sure that only those frequency's that the speaker can reproduce, gets to them. The next part the tweeter, this takes car of all your high frequency's. Having it not actually on the woofer means that you can install it almost anywhere giving you the very best sound angle. Look at ti this way are you looking down at the ground at a concert is that were the music is coming from NO of cores not. That is why tweeters that can be mounted anywhere are better you can put them as if you were at a concert giving you a more true experience with your music. Coaxial, there cheaper and easier to install but not better. These are made for rear fill, or for someone who wants to do a quick and easy install. The tweeters are built right into them. This causes loss of power from the woofer as it can not move as far as one without the tweeter built in. Also it can not sound as good because there is resistance to the movement of the woofer the tweeter being right in the way is what dose this. Also there is usually no crossover to take car of the sound that calls for you to use your high pass on your amp and set it by ear."
Found on the car audio 101 thread
Or
Component
Coaxial