For supply, it is copper and galvanized iron. For waste, ABS (plastic) or cast iron.
Names Pipes and unnamed pipes
Solar panels are divided into two main types depending on the energy they gain - electrical and heat. Obviously this one is gaining heat energy and that is why it has pipes connected to it.
what are the two main types of environment
there are two main types the marine and freshwater
The two main types of friction are kinetic and static.
the two main types of communications are emailing and socialising
The two main types of friction are kinetic and static.
The two main types of economy are Command and Traditional.
what are the two main types of environment
Waste - Vent - water supplyMaterialsCopper - Cast Iron - plastics
In general, the foundations stops (Principal, Diapason, Montre) and the flutes are the two main types of stops on most types of organs. For example, the popular "Roller Moller" has two extended ranks; a Principal and a flute which are unified to many different pitches. However, a theater organist might argue that the strings are used more often in that style of playing than are the foundations. But, I suspect that what you are really asking is what the two main types or organ pipes are. The two main types of pipes are flue (not to be confused with flute) and reed. Flue pipes are simply a whistle with no moving parts. Reed pipes produce sound using a brass tongue not unlike the reeds in a harmonica. Classification of organ pipes break down further much like the taxonomic classification of life forms. For instance flue pipes break down into foundation, flute, string and hybrid. Reeds break down into still more diverse classes.
The two main types of rockets are, Solid Fuel and Liquid Fuel