(a) A continent is a large continuous expanse of land. On a map, continents are depicted as extensive landmasses that cover a significant portion of the Earth's surface. They are surrounded by water but are not considered islands due to their vast size. The seven widely accepted continents are Africa, Antarctica, Asia, Australia, Europe, North America and South America.
(b) An ocean is a large body of saltwater that covers a significant portion of the Earth's surface. Oceans are the largest water bodies on the globe, covering almost three-fourths of the Earth's surface. There are five main oceans, the Pacific Ocean, the Atlantic Ocean, the Indian Ocean: the Arctic Ocean and the Southern (or Antarctic) Ocean.
(c) An island is a smaller piece of land surrounded by water on all sides. Unlike continents, islands are not large enough to be considered landmasses. Islands can vary greatly in size, with some being large enough to host significant populations and infrastructure, while others may be small and uninhabited. An example of a large island is Greenland, the largest in the world.