The Fill Valve is the mechanism that fills the tank with water. It is also known as a Ballcock valve or sometimes a refill valve. It comes in four variations:
Toilet Fill Valves / Ballcocks
The Flush Valve is what releases the water stored in the tank, closes the flow of water into the toilet and allows the tank to refill for the next use. It is the assembly that bolts to the bottom of the tank and includes the overflow pipe and the valve seat. The flush valve has two common variations used to seal the valve seat:
