Here in New Jersey, we have been warned to boil water before using it for drink or cooking as a precaution. When a hurricane or other disaster occurs, water can be polluted and undrinkable. As water is one of the most important resources, having access to clean water is important. Bellow are some suggestions for purifying water. (note: this is for informational purposes only)
1. Boil it / Filter it
This is the easiest and most straightforward way. Simply bring the water to boil and let it boil for 30 seconds. While this kills bacteria, it may release chemicals into the water. You can also filter out dirt with coffee filters or a clean t-shirt.
2. Chlorine Tablets
These tablets can be found online or at sporting goods stores. These do a good job of killing bacteria, but may cause stomach problems in some people. The best use of these is for pre-hurricane preparation when filling a bathtub. Just use some of these to keep the bacteria away.
This device, while expensive, kills bacteria UV radiation. It is more of a flash device though. Being battery powered, it can run out of battery. It also does nothing against chemicals or other pollutants.
Filters come in all sizes. They range from the lifestraw, which are distributed to third world countries for cheap prices, to expensive lifesaver systems which run for hundreds of dollars, or simple filters for water bottles. These provide good filtering from bacteria and other pollutants. They are best used for short term use or for situations when you have to move a lot.