A formal way of creating a UI from a set of functions?

1. What is the function of UI?
2. What are the 3 most important steps in the process to achieving the best UI user experience?

What is the function of UI?

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.

What are the 3 most important steps in the process to achieving the best UI user experience?

The research process may be divided into three main stages: studying problem space, interviewing a client, and analyzing competitors' activities. The key to the project's success is the involvement of all developers and product owners from the very beginning of the process.