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Most of the invisible creatures on Earth do more good than harm.
These microscopic allies do such basic tasks as making soil and oxygen—things we need to live.
Microbes also work for humans in other ways. Some microorganisms, for example, cook up a storm. While they munch on lunch, they create foods for us to eat. In a process known as fermentation, the digestive powers of microbes make foods we would not have without their help. More than 3,500 fermented foods made by microbes exist worldwide. Just a few of them are beer, wine, soda, soy sauce, and dried sausages.
Besides serving as chefs, microbes can be harnessed to work as janitors, pharmacists, gardeners, and more. They can even be used to make stone-washed jeans. (Microbes naturally produce the enzymes used to bleach the jeans.)
