A blueprint for a website’s user interface (UI). Wireframes are simplified sketches—often drawn by hand—of how content and functionality come together in a layout. They focus on how elements are ordered and placed on a page but rarely include specifics about the final visual design. For example, photographs are represented by a box with an X through them. Wireframes are an essential step in responsive web design, since the same elements need to be reordered for different screen sizes.