A continent is a large, continuous area of land with water all around or almost all around it. 70.8% of the Earth's surface is covered by water alone and the other 29.2% is covered by land. This land has been divided into seven main areas called continents. Continents have mountains, rivers, deserts, grasslands, cities, and other landscapes.

There are seven continents on Earth. From largest in size to smallest, they are Asia, Africa, North America, South America, Antarctica, Europe, and Australia. The terms Oceania or Australasia are sometimes substituted for Australia to denote a continent encompassing the Australian mainland and various islands of the Pacific Ocean not part of other continents.

The seven continents are we see today are believed to be a part of a supercontinent called Pangaea around 275 million years ago. Due to the tectonic movement, the landmass broke up and the component continents moved away to their present position. On a closer look, we can find out how the outlines of South America and Africa would fit into each other if joined together.

A supercontinent is a landmass with more than one craton or continental core. Eurasia is a contemporary example; it comprises the traditional continents of Europe and Asia, which are divided by the Ural Mountains.

In the early stages of formation, the center of the Earth was mainly melted iron, and the silica crust was floating on it. So the land drifted around like slow-moving bumper cars repeatedly clustering together and then separating, sometimes forming a supercontinent, and sometimes breaking up into several small landmasses.

The supercontinent Rodinia formed about 1100 million years ago. It broke into several pieces 750 million years ago. Those pieces came back together about 600 million years ago and formed the supercontinent Pannotia. Pannotia broke up into Laurasia and Gondwana 550 million years ago. Laurasia included what are now North America, Europe, Siberia, and Greenland; Gondwana included what are now India, Africa, South America, and Antarctica. Laurasia and Gondwana rejoined approximately 275 million years ago to form the supercontinent Pangaea. Over the next million years, Pangaea broke up into the seven continents we know today.

Continental drift is the movement of the Earth's continents relative to each other by drifting across the ocean bed. The first person to imagine that the continents were joined together before drifting to their present positions was Abraham Ortelius, a Flemish cartographer, and geographer. The concept given by Ortelius in 1596 was further developed in 1912 by Alfred Wegener, a German researcher, and geophysicist. The theory of continental drift was superseded by the theory of plate tectonics.

A subcontinent is a large, relatively self-contained landmass forming a subdivision of a continent. The Indian Subcontinent is a peninsula that juts southward from the rest of Asia like an enormous arrowhead. We call it a 'subcontinent' because it is a distinct landmass, but is not large enough to be considered a continent. Also known as South Asia, it comprises the countries of India, Pakistan, Bangladesh, Bhutan, Nepal, Maldives, Afghanistan, Iran, and Sri Lanka. Sometimes, Myanmar and Tibet are also included in South Asia.

There are a number of islands located on the sections of the continental crust, which have drifted apart from the main landmass. These are too small to be called continents and are hence referred to as micro-continents. Madagascar is the largest example of a micro-continent.

Yes. South America is connected with North America by the Isthmus of Panama. An isthmus is a narrow strip of land connecting two larger land areas usually with water forms on either side. North America and South America are currently considered as separate continents, though in earlier times, they were known as a single continent America.