The word cookie comes from the Dutch word koejke, which means "little cake." However, cookies are truly universal. Whether they are called biscuits in England, galletas in Spain, keks in Germany or biscotti in Italy, almost every country has its own classic cookie. The term covers such a myriad of morsels that it is difficult to define. A very broad definition of cookie is a flour-based, hand-held sweet treat that can range from a thin, crisp butter round to a one-inch-thick cakey bar cookie. Cookies can be eaten as a snack, dessert or with afternoon tea. Special cookies are often tied closely to holiday traditions and family celebrations.

The seemingly endless variety of cookies can be divided into five basic types: bar, drop, refrigerator, rolled and shaped.

These cookies are made by spreading or pressing a batter or soft dough into a baking pan. After baking, cookies are cooled, sometimes frosted and cut into squares or rectangles. One reason for the popularity of bar cookies is their ease of preparation. Always use the size pan specified in the recipe to ensure proper doneness. If using a glass baking dish instead of a metal baking pan, reduce oven temperature by 25°F. For easier cutting and cleanup, line the baking pan with foil, allowing the foil to cover the sides of the pan. Grease the foil if the recipe directions recommend greasing the pan. After baking and cooling, remove the cookies from the pan using the foil. Peel off the foil. Place the cookies on a cutting board and cut as directed.

Made by dropping spoonfuls of thick dough onto a baking sheet, drop cookies are the most common type of cookie in the United States, with chocolate chip and oatmeal raisin dominating. Use regular tableware rather than measuring spoons for dropping dough. To easily shape dough, use an ice cream scoop with a release bar. The handiest sizes for cookies are 40, 50 and 80. The size usually is stamped on the release bar. Cookies that are uniform in size and shape will finish baking at the same time. Space dough 2 inches apart on baking sheets to allow for spreading, unless the recipe directs otherwise.

The dough is shaped into logs, refrigerated until firm and then sliced for baking. Shaping is easier if you first place the dough on a piece of waxed paper or plastic wrap. Then roll it back and forth to form a log. Before chilling, wrap the rolls securely in plastic wrap to prevent the dough from drying out. To keep a log of cookie dough round during slicing, roll it a quarter turn every four or five slices. For easier slicing, finely chop the ingredient pieces, such as nuts and fruit.

The dough is rolled with a rolling pin until it is a certain thickness, usually 1/8- to 1/4-inch thick. Then the dough is cut into shapes with cookie cutters. Chill the cookie dough for easier handling. Remove only enough dough from the refrigerator to work with at one time. Save any trimmings and reroll them together to prevent the dough from becoming tough. To minimize sticking of dough when using cookie cutters, dip cutters in flour or spray with vegetable spray. After baking, these cookies are often frosted and decorated.

Shiny, heavy-gauge aluminum baking sheets promote even browning of cookies; dark pans absorb more heat causing cookies to brown too quickly. To use dark sheets, reduce oven temperature by 25°F. Nonstick finishes minimize sticking and make cleanup easier.

Grease baking sheets only if directed to do so in the recipe. Most cookie recipes are high enough in fat that they will not stick while baking. Use vegetable shortening or nonstick vegetable spray. Grease sheets for cookies that are rolled in sugar since sugar scorches easily.

Preheat oven to desired temperature about 15 minutes before beginning to bake. For even baking and browning, place only one baking sheet at a time in the center of the oven. Allow at least two inches of space between the baking sheet and the wall of the oven for proper air circulation. If the cookies brown unevenly, rotate the cookie sheet from front to back halfway through the baking time.

When baking more than one sheet of cookies at a time, rotate them from the top rack to the bottom rack halfway through the baking time.

When reusing the same baking sheets for several batches, cool the sheets completely before placing dough on them. Dough will soften and begin to spread on a hot sheet.

To avoid overbaking cookies, check them at the minimum baking time. If more time is needed, watch them carefully to make sure they do not overbake. It is better to slightly underbake than overbake cookies.

Cool individual cookies on a wire rack. If the cookies seem too tender or begin to fall apart when removed from the pan, allow them to cool a minute or two before transferring to the cooling rack. Cool bar cookies in their pan, unless the recipe directs otherwise.

Completely cool all cookies before storing in airtight containers. Store each kind of cookie separately to prevent transfer of flavor and changes in texture.

To keep moist cookies soft, store them in a tightly covered container for a day or two with 2 or 3 thick apple slices. Remember to remove the apple slices at the end of the two- or three-day period. Apple slices may also be added to a storage container to soften stale or overbaked cookies.

Most cookies freeze well for several months. Store unfrosted cookies in sealed plastic bags or airtight containers with plastic wrap or waxed paper between layers of cookies. Most cookies thaw at room temperature in 10 to 15 minutes.