A piece of cheese is a piece of cheese, so is a loaf of cheese also a piece of cheese? Is there any difference between piece and loaf? So why is a piece of bread a loaf of bread? And bar

A piece of cheese is a piece of cheese, so is a loaf of cheese also a piece of cheese? Is there any difference between piece and loaf? So why is a piece of bread a loaf of bread? And bar

A piece of cheese
A loaf of cheese
A piece of bread
A loaf of bread
A bar of chocolate