How does a glacier differ from an iceberg?

The relationship is mother and daughter. A glacier is the mother of an iceberg, much bigger and much older. The glacier is a vast area of frozen snow and ice, often covering many square miles. It may spread flat over the land or it may hang like a frozen river on a mountain slope. Many of the world’s glaciers spread out and finally meet the sea   and these are the ones which produce daughter iceberg6.

The pounding ocean waves undermine the glacial ice and great chunks break off and fall into the sea. This event is the birth of an iceberg. The floating chunk of ice drifts with the currents and finally melts.