The mouli grater serves some of the same purposes as a blender or food processor. It could be compared to a small, manual food processor, or a linear standard food grater. Where a flat food grater, such as a cheese grater, might be used to grate a large amount of food, the mouli grater generally is most useful for grating the volume of food that fits into its small chamber. A mouli type grate might be used to crush a small amount of some garnish or flavoring ingredient, such as garlic, although specialized garlic presses exist for that purpose as well.
The mouli type of grater consists of two hinged parts. A crank turns the grater and mashes food inside the central space. The inner part of the device is often called a food hopper. The other part of the mouli grater mashes the food into the hopper.