Anaerobic organisms are living beings that thrive in environments without oxygen. They can be found in various habitats, such as deep soil, marshes, and the intestines of animals. These organisms obtain energy through processes like fermentation or anaerobic respiration, allowing them to survive where oxygen is absent. Examples of anaerobic organisms include certain types of bacteria, such as Clostridium and Bacteroides. These microorganisms play essential roles in ecosystems, such as breaking down organic matter and recycling nutrients. Some anaerobic organisms are also used in industrial applications, like producing biofuels and probiotics.