• Typical Coral Reef"Swim by shooting" is Copyrighted by Flickr user: rumpleteaser (Cat) under the Creative Commons Attribution license.
  
  

History

• The study of coral reefs goes back only about 300 years, according to Encyclopedia Britannica. In 1727, French naturalist Jean André Peyssonnel became the first to declare the coral reefs a living entity. Prevailing thought before Peyssonnel considered the coral reefs a plant and navigational hazard. In 1842, naturalist Charles Darwin put forth a theory on how coral reefs grow and the different stages, or types, of coral reef.
  
  

Identification

• Coral reefs are made up of tiny organisms called polyps that create calcium skeletons, according to the National Oceanic and Atmospheric Administration. Coral polyps contain single-cell algae that produce oxygen for the polyps and help them build a calcium skeleton. Many polyps can grow together and form a colony commonly called a coral reef. Coral reefs are among the largest biological structures in the world.
  
  

Fringing

• Fringe coral reefs are the most common type of reef. Almost all coral reefs grow and expand from coral larvae attaching to coasts and shores. Fringe reefs usually jut out of the sea and form a visible border along the shoreline or around an island. A shallow amount of water, shallow enough for a person to wade or walk around, often separates a fringe reef from land.
  
  

Barrier and Atolls

• Barrier reefs often look like fringe reefs, but barriers are bigger, grow much farther from coastal lines and have a deep lagoon that separates the reef from land, according to National Oceanic and Atmospheric Administration. A third major type of reef called an atoll forms around the ring of a submerged volcano. The atoll grows upward and sometimes emerges from the top of the sea to form island-like masses. A fourth type of reef, a patch reef, forms patches of reef in a lagoon.
  
  

Potential

• The website stanford.edu, reports that one-third of all reefs face extinction. Reefs are more important than just being structures in the ocean. Reefs support more than 1 billion people in the world with food and employment. Pollution and overfishing are damaging coral reefs to the point that they either cannot recover or become less productive and weaker. Humanity's growing population will need more resources from ever shrinking coral reefs.