Tankless water heater

The main difference between them is that the traditional water tank stores and preheats the water while a tank-less heater uses a heat source to warm up cool water on-demand whenever you need it rather than storing hot water in a tank. While the tank-less heater has high initial cost in the long run it saves money. Also as it has no tank it takes up only lesser space. And again it lasts longer and gives water on demand. I installed mine from High Efficiency Inc. For more details you can check out some brochers of tankless heaters.