A lean-to is a simple structure that is typically built against an existing wall or building. It features a slanted roof that allows rain and snow to run off easily. Lean-tos are often used for storage, as shelters for animals, or as additional living space. They can be made from various materials, including wood, metal, or even canvas. These structures are popular in outdoor settings, such as campsites or gardens, where they provide protection from the elements. Lean-tos are also commonly found in rural areas, serving as functional spaces for tools and equipment. Their straightforward design makes them easy to construct and maintain.