Steak and kidney pie in the context of "Scotch pie"

A Scotch pie is a double-crust meat pie, traditionally filled with minced mutton (whereby also called a mutton pie) but now generally beef, sometimes lamb. It may also be known as a shell pie to differentiate it from other varieties of savoury pie, such as the steak pie, steak and kidney pie, steak-and-tattie (potato) pie, and so forth. The Scotch pie originated in Scotland, but can be found in other parts of the United Kingdom and abroad.