A food grinder is a kitchen appliance used for making ground food items. There are different grinding machines for different needs. For instance, vegetarian items are soft hence they can be grinded with hands. There would be no difficulty in grinding vegetarian items with a knife but for meat, you need a grinding machine.
Visit here:- http://www.imfaceplate.com/ButchersEquipment/an-introduction-to-meat-grinding-machine