Rain-X

While I was driving my truck through the rain I noticed that the rain was beading up and blowing off the windshield. I then remembered that I put Rain-X in my windshield wiper fluid. The Rain-X applied a thin film to the windshield that prevented the rain from sticking. The Rain-X is most likely a neutrally charged, organic fluid similar to an oil which would prevent the extremely polar water molecules from sticking and smearing on the windshield. Since the water molecules couldn't stick to the glass they stuck to each other and formed tightly packed beads. These tight beads were formed due to water's high surface tension behavior. The Rain-X repelling the polar water molecules and water beading up on the windshield greatly increased my visibility and provided a safer drive.