The answer to 'what is retaining wall' is a structure designed to hold back soil or other material on an elevated slope. Retaining walls are commonly used in landscaping to create terraced gardens, raised planting beds, or to stabilize hillsides. They are typically made of concrete, stone, brick, or treated wood and are built to withstand the lateral pressure of the soil or material they are holding back.
Retaining walls serve several important functions in a landscape, including preventing erosion, increasing usable space, and enhancing the visual appeal of a property. They can be built in a variety of styles and designs to complement the overall aesthetic of the home and surrounding landscape.