Icebergs are masses of ice that detach from a glacier or ice shelf into a lake or the ocean. Icebergs typically come in two shapes: tabular, with steep sides and a flat top, and non-tabular, which come in a variety of shapes with domes and spires. 

Icebergs as large as 80 kilometers long have broken away from Antarctic ice shelves. Smaller chunks of ice from glaciers are called bergy bits (less than 5 meters) and growlers (less than 2 meters). 

Scientists and decision-makers use NASA data to track and study icebergs because they are common components of cryospheric and marine ecosystems. They have a role in weather and climate and can be a hazard to maritime safety.