The document discusses different types of turbines. It describes the Francis turbine in detail. The Francis turbine is a mixed-flow reaction turbine used for medium heads and speeds. It has components like a penstock, scroll casing, speed ring, stay vanes, guide vanes, runner blades, and draft tube. Water enters the scroll casing and is directed by the guide vanes towards the radially inward curved runner blades to extract energy before exiting through the draft tube. The document also briefly describes the Kaplan turbine, an axial-flow reaction turbine suitable for low heads. Both the guide vanes and runner blades of the Kaplan turbine can be adjusted for high efficiency.