The term 'pool cover' can be summarized as a tarp, which is a four-letter word. A pool cover is a protective covering that is placed over a swimming pool to keep debris and dirt out of the water. It also helps to maintain the temperature of the pool and reduce evaporation. Pool covers come in a variety of materials, including vinyl, mesh, and tarp. Tarps are the most common type of pool cover because they are lightweight, durable, and easy to install.