Rico in Spanish means rich in English just if your talking about money. If your talking about food rico means it's delicious, good, etc. Example, esto huele rico mean this smell good or  que Rica la comida means like delicious food in English. Puerto Rico means Rich Port in Spanish.
Tankless or demand-type water heaters heat water directly without the use of a storage tank. Heat pump water heaters move heat from one place to another instead of generating heat directly for providing hot water. Solar water heaters use the sun's heat to provide hot water.
Tankless water heater is designed in a way that when you start the tap you will get the hot water as it is tankless so you need not have to worry about the water. And Since tankless models only heat up the water when it is required, they're much more efficient than the storage types.