Nonstick cookie sheets are the most commonly used. When you are choosing a nonstick cookie sheet pick them out by the composition of the nonstick finish and by the color. Darker finishes will bake cookies darker and lighter finishes will produce lighter colors in cookies after baking.
Nonstick cookie sheets will bake cookies quicker than other baking sheets but can bake them drier as well so you need to be cautious to not over bake them. Also, clean up is easy but after each cleaning check the surface to ensure the finish is still intact before using and replace when the nonstick finish begins peeling; you don’t want to bake with the pan if the finish is peeling off.
Aluminum cookie sheets can come in different styles such as rolled edges, edgeless and very high sides. Aluminum cookie sheets bake cookies uniformly since the aluminum metal properties conduct heat well. Highly acidic cookie doughs can have a negative reaction and produce a metallic flavor once the cookies are baked, so a silicone baking sheet is recommended as a barrier during baking. Cookie sheets made with a thicker aluminum will hold heat better than thinner ones and will keep cookies warmer longer once removed from the oven.
Insulated cookie sheets have a thin layer of air, or a hollow space between two metal layers. Baking cookies on these sheets are best reserved for very delicate cookies since they tend to bake slowly and require less browning; so you shouldn’t use this pan for baking chocolate chip cookies. However, if you use insulated cookie sheets for baking with standard cookie dough, remove them as soon as they brown around the edges or they will over bake and become hard.