A delta is a landform that occurs at the mouth of a river, where the river meets a larger body of water, like an ocean or a lake. As the river flows, it carries sediment—tiny bits of soil and rock. When the river slows down at the delta, it drops this sediment, creating new land. Deltas are often shaped like a triangle or fan, which is why they are named after the Greek letter Delta. Deltas are important ecosystems that support diverse wildlife and plant life. They provide habitats for many species, including fish, birds, and other animals. Additionally, deltas are crucial for human activities, such as fishing, agriculture, and transportation, making them valuable for both nature and communities.