A mixer is a kitchen utensil which uses a gear-driven mechanism to rotate a set of beaters in a bowl containing the food to be prepared. It automates the repetitive tasks of stirring, whisking or beating. When the beaters are replaced by a dough hook, a mixer may also be used to knead. A mixer may be a handheld mechanism known as an eggbeater, a handheld motorized beater, or a stand mixer. Stand mixers vary in size from small countertop models for home use to large capacity commercial machines. Stand mixers create the mixing action by rotating the mixing device vertically: planetary mixers, or by rotating the mixing container: spiral mixers. Mixers for the kitchen first came into use midway through the nineteenth century; the earliest were mechanical devices. The demand from commercial bakers for large-scale uniform mixing resulted in the development of the electric stand mixer. Smaller counter-top stand mixers for home kitchen use soon followed. When selecting a mixer, the purchaser should consider how the mixer will be used. Electric mixers with more speed options give the user more control over the development of the mixture.