Continents are large landmasses that make up the Earth's surface. There are seven main continents: Asia, Africa, North America, South America, Antarctica, Europe, and Australia. Each continent has its own unique geography, climate, and cultures, making them diverse and interesting places to explore. Islands are smaller landforms surrounded by water. They can be found in oceans, seas, and lakes. Some well-known islands include Hawaii, Madagascar, and Greenland. Islands can be formed by volcanic activity, coral reefs, or the rising and falling of sea levels. They often have rich ecosystems and can be home to many unique species.