i mean there are Linear tapers and Logarithmic's.
Depend what you're using it for. Typically you'd use a log taper pot for a volume control, because your ears have a logarithmic response - if you used a linear pot it would get very loud very quickly, and then most of the control wouldn't make much difference.
You might use a linear pot for something like a tone control, where you want the effect to be directly proportional to the position of the knob. You even get anti-log pots which build up quickly and the flatten off, which are good for things like distortion controls.
What will really blow your mind is that you can fake a lot of these responses by adding resistors in parallel with the slider and one or other end of the pot! That way you can come up with some really peculiar responses, which might be what you need in some cases. There's nothing worse for control feel than having something where all the useful range is in the first quarter turn...
It's worth reading up a bit about basic electronics. You don't need to know much, just the basics - but if you don't know the basic theory you can spend a lot of time staring at stuff that doesn't work without even the ability to start to guess why.
Ohm's Law is something you need to learn. It's simple, and it explains about half the things you're going to ask.