User interface is all about making it easy for the users to understand how to successfully accomplish their tasks. One page that I really like to see is this one from Xerox: 35 Interfaces That Changed Our World There you’ll see that a User Interface isn’t just visible on the web, in fact is much more than that.
User interfaces are the way we interact with products. Most people think of user interfaces as being the visual interfaces we see on the screens of our devices (known as a Graphical User Interface, or GUI), but interfaces stretch far beyond that. Some other examples of user interfaces include voice interfaces—such as the voice assistants from Google, Apple, Microsoft, and Amazon—tactile interfaces such as mice, dials, keyboards, buttons, and scroll wheels (e.g. those found on some iPods).
“Visualization is the most powerful tool”.
UI is all about how far you can imagine the interaction between human and machine. To leverage this interaction UI plays and important role.
The more powerful imagination the more powerful would be the solution to a problem using the UI.
There is a beautiful article written by Kim Thuy Tu about the User Interface:
I hope this helps you in framing a better mind towards the UI and unleash your creative potential.