A sifter is a kitchen utensil with a mesh bottom used to sift dry ingredients, such as flour or powdered sugar. The most common sifters are built with a trigger in the handle that is activated to move back and forth in order to push and pull the dry contents through the mesh sieve in the bottom of the sifter. Sifting is done to break up any lumps in the flour, which means you can get a more accurate measurement. Sifted flour is also much lighter and airier than unsifted flour and is easier to mix into other ingredients when making batters and doughs. Sifting flour without the addition of other ingredients separates and helps to add lightness in the form of air, something desired in most baked goods. It also helps to remove clumps. Sifting is the key to light-as-air cookies, cakes, and all your best pastries. Sifters are also used to add air to the dry ingredient in order to make it lighter and more uniform in texture, resulting in improving the baking or food preparation results.

In summary, a sifter is used to sift dry ingredients, such as flour or powdered sugar, to break up any lumps, remove clumps, and add air to the dry ingredient to make it lighter and more uniform in texture, resulting in improving the baking or food preparation results.