By tunnelling through the compost pile, worms increase the availability of oxygen and the compost pile's ability to retain moisture. They also produce benevolent bacteria in such overwhelming numbers that disease producing bacteria find life extremely difficult. The most common 'composting' worms are the Red, Tiger, and Blue Worm. All are ferocious eaters and rapid breeders. All are commonly available from most nurseries.
Worms eat up to their own body weight each day.
Their by-products are called vermicast. Vermicast is an excellent fertiliser for plants - better than pure humus and it, too, is quite free of pathogens. A worm population can double in 7 - 8 weeks. This means that their processing of the contents of the chamber increases exponentially. When their food supply declines, the population diminishes, leaving a chamber full of vermicast.