I like to use a rimmed cookie sheet—it’s called a half sheet pan—for most of my cookies. But a rimmed pan is not the best choice if you’re baking light and delicate cookies like lace cookies because those are often hard to lift of the pan if there is rim in the way.
In general, heavy-duty aluminum cookie sheets conduct heat well, and the shiny, reflective surface helps cookies bake evenly. If you have dark cookie sheets, they can cause the bottoms of the cookies to get too brown because the dark color absorbs the heat more quickly than lighter-colored pans.
For more cookie tips, see Top 10 Cookie Secrets.
Recipe: Jam-Filled Mezzaluna Cookies