The document defines and describes several basic terms used in UX design including customer personas, user journeys, user flows, prototypes, and different types of prototypes. Customer personas are representations of ideal users, user journeys map the stages a user goes through when interacting with a product, user flows show the steps a user takes to complete a task on a website or app. Prototypes are early versions of a product that are improved through iterations and come in different forms from paper prototypes to high and low fidelity digital prototypes.