The user interface (UI) is the point of human-computer interaction and communication in a device. This can include display screens, keyboards, a mouse and the appearance of a desktop. It is also the way through which a user interacts with an application or a website.
A version of a new product which allows a team to collect the maximum amount of information about customers with the least effort. Seeing what people actually do with respect to a product is much more reliable than asking people what they would do.
Content that appears on the top half of a website or terminal window.