Whales are large marine mammals that belong to the order Cetacea. They are known for their incredible size, with some species, like the blue whale, being the largest animals on Earth. Whales are found in oceans all over the world and are divided into two main groups: baleen whales, which filter food from the water, and toothed whales, which hunt for fish and squid. These magnificent creatures are also known for their complex behaviors and social structures. Many species, such as the humpback whale, are famous for their beautiful songs, which they use to communicate with each other. Whales play a vital role in maintaining the health of marine ecosystems.