Where can microbes be found, even though no other life-form exists?

Microbes are present everywhere – in soil, water, air, inside our bodies and that of other animals and plants. They are present even at sites where no other life-form could possibly exist–sites such as deep inside the geysers (thermal vents) where the temperature may be as high as 100 degree C, deep in the soil, under the layers of snow several metres thick, and in highly acidic environments.