The main difference between pool tile and regular tile is durability. Pool tile needs to withstand being submerged in water, blasted by UV rays, exposed to harsh pool chemicals, and be able to hold out against huge temperature fluctuations and severe weather, which regular tile used in a kitchen backsplash or bathroom does not need to withstand. Additionally, pool tiles need to meet certain standards such as water absorption, thermal shock, and other standards that regular kitchen or bath tiles may not need to meet.