Manual grinders are hand-operated with a crank or lever and are less expensive than electric ones. They tend to be portable and can only grind small quantities of coffee beans at a time. They also are quieter and do not produce as much heat as electric grinders, which can impact the flavor of the coffee. Electric grinders use a motor to power the grinding and are faster than manual grinders. Electric grinders have more precise settings and are larger and more expensive than manual ones.