This is more a matter of colour and material. Look for a label with washing instructions.
warm water
paper towels can be used for lots of things. its mostly used to clean up spills, messes, and to wash up. it actually helps helps keep your hands clean after you wash your hand with water and soap. Paper towels can be recycled and reused.
Wash towels in hot water using normal detergent with 1/2 cup of borax.
Ideally, you should wash your bath towels within 24 hours - as the dampness remaining in the towels following a bath or shower, can - if left too long, cause the towels to become smelly, or even develop mildew. Of course follow the care labels on your towels, but it's best to wash in warm water, and without any fabric softener - which will remove the drying properties of your towels over time.
It should be a cold temperature.
Hot water soap and paper towels
The temperature of the water is lower than the air temperature. [Try running the hot water a little before you wash your hands.]
In addition, washing towels separately will mean that you can wash them on a slightly higher temperature, and not cause the "fluff" from them to get on other clothes. The use of chlorine bleach with towels is best only on white towels - you can use colo(u)r safe bleach on non-white towels, or a mixture.
i don't know that there are necessarily four categories but you definitely need to split them into light and dark at least. I group mine into black\navy, whites that can be bleached, lights, and bue/green. i have alot of jeans so i wash them together. also i never wash towels with my clothes. i wash everything except the towels in cold water. it saves on your water bill and prevents shrinkage or fading. but towels need hot water in my opinion.
Wash them
Sometimes but most of the time the hair quality depends on the shampoo you use.
viva towels will soak up more than most paper towels,but what they don't want you to know is that you can wash them out after use and reuse them again.... try it... don.
its up to you but it doesn't really matter