When invited to “drop by for a cup of coffee,” it is not essential to take anything, unless you happen to have some home–baked goods or a small bouquet of flowers from your garden. A formal afternoon tea–given to honor a houseguest, welcome new neighbors, or celebrate some event–requires formal dress (dress or suit for the women and business suit for the men). It is not essential to take a gift, for you can always reciprocate later in some way.