A vinyl liner pool is a type of swimming pool that features a flexible, waterproof liner made from vinyl material. This liner is custom-fitted to the pool's shape and is installed over a structure, typically made of concrete, steel, or polymer. Vinyl liners are available in various colors and patterns, allowing for aesthetic customization. These pools are popular due to their affordability and ease of installation compared to other types, such as concrete or fiberglass pools. However, they may require periodic replacement of the liner, usually every 5 to 9 years, depending on maintenance and environmental factors.