A user interface is an important part of the software because it determines how easily and how quickly a person understands and manipulates the software. It simplifies the commands that the user gives.
The user interface is software.
user interface
Application programming interface software
User interface
Area on the screen where the user interacts with the software application is known as ~
An user interface.
A user interface (UI) is the part of an operating system, program or device that the user uses to input and receive data
user interface
the operating system
shell
A user interface can be software or hardware, but it is mainly software. It will depend on the situation. If you are entering directly through a keyboard, it could be hardware, but software can also be considered, as the screen layout is designed by software and that is determining where you type on the screen, like the locations of text boxes, and it has the prompts and it is validating what you type in. We use hardware to enter data, but the actual user interface can be considered as software, though they are obviously linked.
To execute code and provide a graphical user interface.