Drumlins are elongated hills formed by the movement of glaciers. They are typically made up of sediment and are shaped like a teardrop, with a steep side facing the direction the glacier came from and a gentler slope on the opposite side. These unique landforms can vary in size and are often found in groups, creating a landscape that tells the story of past glacial activity. The study of drumlins helps scientists understand the behavior of glaciers and their impact on the environment. They are often associated with other glacial features, such as moraines and eskers, and can provide valuable insights into the history of Earth's climate during the last ice age.