What are some common methods of water purification?

In the wilderness, this is the most common and reliable method of wilderness water treatment. Boiling water sufficiently for 1-2 minutes kills disease-causing microorganisms.

Advantages: effective sterilization and low cost. As long as you have a pot, a stove and fuel or firewood for living, it's no problem to boil as much as you want, completely independent of location.

Disadvantages: not all drinking water is available by boiling, and unless you're staying in a base camp, it's not very convenient. It takes time and fuel to boil large quantities of water, and you have to let it cool before you can drink it. At base camp there is the option of boiling water at night and having treated drinking water in containers, but it's not an easy job. Also, the oxygen is boiled out of the water as it boils, making it tasteless.

Outdoor water purifiers

You can opt for a filter that is simple to use. However, it is worth noting that if you need to filter out Cryptosporidium and Giardia, you need to choose a filter with a pore size of less than 1 micron to do so.

Benefits:

Treated water is cool, ready to drink without waiting, and tastes good. Filters are much lighter than containers filled with clean water, so they're good for places where surface water can be found regularly.

Disadvantages:

The weight of the filters varies widely, ranging from 70-700 grams, and some are a bit heavy and not cheap. They also require frequent cleaning, and regular replacement of the filter cartridge.