Water quality, temperature and proportion are important to a great cup of coffee.
Water is the stuff of life, and that goes for humans, fish, monkeys and cups of coffee. Before you even think about the beans, you need to make sure your water is top notch. Make sure it's cool and filtered. Never start out with warm or hot water when using a drip machine - the temperature plays a big role in the end taste, and being too hot can ruin your morning brew. If you want your coffee to taste pure, you must filter your water. As we've discussed previously, hard water or softened water will leave your coffee with an odd aftertaste. So when you've got the right stuff, make sure you're using the proper amount. The general rule of thumb is one to two tablespoons of coffee per six ounces of water, but exact measurements will be up to your personal preferences.
That's all you need to know about water unless you're a chemist, in which case you should probably know a few other things. For those of you solely interested in water as a vital coffee ingredient, that should about cover it.