Hey Rico, I hope this helps you. custom (noun): the usual way of acting/being (It is a custom for brides to wear white wedding dresses) customs (noun): taxes or fees paid to a country/ government when products/goods come into or out of a country (I went through customs at the airport without any problems) custom/ customized (adjectives): made/ changed specially for individual customers/needs/taste etc (I bought a custom/ customized kitchen) So in the adjective forms, you can use both in the same way. In England we use customized as the adjective (a customized website), whereas in the US I believe custom as an adjective is used more (a custom website). The verb however is always to customize, in both countries (not to custom). Let me know if you have any questions!