What are Coral Reefs

Corals are coelenterates living in limy skeletal cup which is secreted by the epidermis. After the death of organism, their skeleton, which is made up of calcium carbonate deposited at the bottom of seas. After thousands of years, they form rock like deposits known as coral reef. Sometime it causes accidents in sea.

For example, L. Tolstoy’s novel “Anna Karenina” costs about UAH 200 in bookstores, and the electronic version can be downloaded absolutely free of charge. Considering that it takes 3-4 days to read a novel, the financial costs of imperishable masterpieces in print can be equal to the average salary of our compatriot. At the same time, the purchase of an electronic resource will pay off in 1-2 months. Electronic and printed books