Too many people have to worry about the overall quality of the water that they drink and cook with on a daily basis. Water supplies are becoming more and more contaminated with things too horrifying to even mention, and yet the problem only gets worse despite the available information. While this is rarely a problem in the city where the quality of water is generally much higher than what people are drinking in the rest of the country, it becomes a much bigger issue if you live in, for instance, the Midwest. In smaller towns and cities, the control kept over the water supply is generally much more lax because of a simple lack of resources, so people that live in this part of the country have to watch out for themselves to a large extent.
Thankfully, there are a number of water dispenser products on the market aimed at allowing people to do just that: Give themselves a lot more peace of mind regardless of the water quality in their immediate surroundings. Generally, such a person will want to look for a high quality dispenser unit, either bottled or bottle-less. If you go with the bottle-less unit, the water will come from your local plumbing supply. Of course, this means you are relying on the questionable water again. However, these units generally come with a filter, operating similarly to a whole house water filter. These units generally use some form of reverse osmosis for water cleaning, while others will rely on complex networks of carbon blocks and sediment filters in replaceable filter media.
If you go with the bottled variety of water cool, you will completely cut your local water supply out of the equation, relying instead on deliveries of water that was cleaned in a large plant with lots of safety regulations.
Whatever you choose, it comes down to your unique circumstances. Either way, be sure to make some kind of decision to better the drinking water in your house if you live in an area where the water supply is questionable!