Crackers are eaten on their own or can accompany other food items, such as cheese or meat slices; dips; or soft spreads such as jam, butter, or peanut butter. Bland or mild crackers are sometimes used as a palate cleanser in food product testing or flavor testing, between samples. A precedent for the modern cracker can be found in nautical ship biscuits, militaryhardtack, and sacramental bread.
The holes in crackers are called "docking" holes. The holes are placed in the dough to stop overly large air pockets from forming in the cracker while baking. Crackers come in many shapes and sizes - round, square, triangular, etc.
In American English, the name "cracker" is most often applied to flat biscuits with a savory, salty flavor, in distinction from a "cookie", which may be similar to a "cracker" in appearance and texture, but has a sweet flavor. Crackers may be further distinguished from cookies by the manner in which they are made. Crackers are made merely by layering dough and cookies may be made in many of the same manners a cake would be prepared. Crackers sometimes have cheese or spices as ingredients, or even chicken stock. Crackers are typically saltedflour products.