Coral reefs might look like colorful rocks or plants, but they are actually built by millions of tiny living creatures called «coral polyps», which live together in large colonies and build hard calcium structures around their bodies.
Over time, these tiny structures pile up on top of each other to form a massive structure called a «coral reef», usually found in warm, shallow waters near the equator, where sunlight reaches easily.
Coral reefs are among the richest habitats for life in the ocean, home to thousands of species of colorful fish, snails, and starfish. The world's most famous reef is the «Great Barrier Reef» near the coast of Australia — one of the largest living structures on Earth, visible even from space.
