What is windowsill?

A windowsill is the horizontal surface at the bottom of a window. It is usually made of wood, metal, or stone and serves as a ledge on which items can be placed, such as plants or decorative objects. In addition to its aesthetic value, a windowsill can also provide insulation and protect against moisture. Some windowsills are sloped to allow for water drainage, while others have built-in channels or grooves to collect condensation. In older buildings, windowsills may also have historical significance and be considered architectural features.