Benthic organisms are living creatures that inhabit the bottom of oceans, rivers, lakes, and other bodies of water. They include a variety of species such as crabs, clams, sea stars, and bacteria. These organisms play a crucial role in the ecosystem by breaking down organic matter and recycling nutrients. These organisms can be classified into different groups based on their size and lifestyle. For example, macrofauna are larger benthic organisms, while microfauna are microscopic. Benthic organisms are essential for maintaining the health of aquatic environments and contribute to the overall biodiversity of marine and freshwater ecosystems.