J. Kenji Lopez-Alt

Batters are made by combining some sort of flour - usually wheat flour, though cornstarch and rice flour are not uncommon - with a liquid and optional leavening or binding ingredients, like eggs and baking powder.

American Chef

Cornstarch is primarily used in cooking to achieve a thicker consistency in liquids like soups and sauces.

Culinary Thickener

Cornstarch needs gentle heat to activate thickening but can become clumpy if heated too quickly.

Heat Activation

To prevent clumps, cornstarch is often mixed with cold water before adding to hot liquids.

Clumping Avoidance

In industry, cornstarch is not just for food but is also key in manufacturing paper and textiles.

Non-Food Uses

Cornstarch is favored in 'green' products because it's biodegradable and a renewable resource.

Biodegradable Material

Cornstarch in paper production results in a smoother, stronger paper, often used in glossy prints.

Paper Coating

 These mountains of maize inspired numerous corn concoctions. Cornstarch could be used as a thickening agent for everything from gasoline to glue or processed into a low-cost sweetener known as High-Fructose Corn Syrup. Maize quickly became one of the cheapest animal feeds worldwide. This allowed for inexpensive meat production,

The history of the world...

 You can use flour and water, or cornstarch and water. I actually found three separate recipes in the literature. My favorite being the one that says -- you know, they have the ingredients listed, and then in a recipe it will say, for example, two dozen cupcakes." This one said, one ejaculate."

Mary Roach: 10 things...

 custard utilizes ingredients that we tend to have a lot of so I want to teach you how to make custard all you need is milk eggs and honey and then you can add some flour or cornstarch and some vanilla okay all right let's just use up