Cream together the butter, brown sugar, and white sugar until smooth.
Beat in the eggs one at a time, then stir in the vanilla.
Combine the flour, baking soda, and salt; stir into the creamed mixture.
Stir in the oats.
Drop by tablespoonfuls onto ungreased cookie sheets.
Bake for 10 to 12 minutes in the preheated oven. Allow cookies to cool on baking sheet for 5 minutes before transferring to a wire rack to cool completely.
Interesting Facts
Oatmeal cookies are believed to have originated in Scotland.
Oatmeal cookies are a type of drop cookie.
Oatmeal cookies can be made with either rolled oats or quick-cooking oats.
Oatmeal cookies can be flavored with spices, such as cinnamon or nutmeg.