An iceberg is a large piece of ice that floats in water. It may have been broken away from a glaciers or ice-shelf. The word iceberg probably means ice-hill. The tallest iceberg ever measured was 168 mts high.
Small icebergs are known as growlers, because of the noise they make.
About 10,000 to 15,000 new icebergs are formed every year. The process of breaking away is called "Calving".
Seven eights of an iceberg is below the surface of the sea.
Icebergs float because, they are made of fresh water which is less dense than the sea water.