Coral reefs represent a breath-taking landscape, especially for those who love the exotic lands. Usually people associate the coral reefs with crystal water and sunny beaches full of white sand. Most of the coral reefs can be found in the hot seas - in places where the temperature of the water is above 20 degrees. Corals actually are skeletons of little organisms which the experts call "polyps".
Because of these micro-organisms, the reefs are developing across the years. Experts say that the reefs cover about 0.2% of the oceans and are considered the home of numerous marine species. It is an important attraction for tourists in countries where the corals exist: Australia, Egypt and Japan. Coral reefs are sorted in many types, but the most popular divides them in four groups. There are platform reefs, fringing reefs, barrier reefs and atolls (which are not so beautiful like the first two groups).
The fringing reefs represent that group of coral reefs that can be found in shallow waters, near the shore. They are usually separated from the shore by a narrow strip of water. Apart from the platform reefs, are situated far from the shore, even at ten of kilometers. These types of coral reefs have a flat form (they look just like a platform). The Barrier reefs form parallel to coastlines and usually are separated from the coast by a lagoon. These coral reefs impress by their dimensions which are very big. The last group of coral reefs is represented by the atolls. They have a circular form and generally encircle islands. Atolls form in the deep sea and they rise from the ocean. They can be found on the continental shelf. Coral reefs are a wonder of nature and they must be protected because of their beauty.
