Preheat oven to 350°.
Grease cookie sheet.
Sift together flour, baking soda, and cream of tartar.
Set mixture aside.
Beat together butter and sugar until fluffy.
Beat in eggs and vanilla.
Gradually add flour mixture.
Drop onto cookie sheet, using rounded tablespoonful for each cookie.
Bake for 12 to 15 minutes or until lightly golden brown.