Interacting with Computer Systems
The buttons you created on the brain's screen are the beginning of a basic Graphical User Interface (GUI). There are other types of User Interfaces (UIs), but we will focus on GUIs because they are the type we use most.
A UI is a space that allows the user to interact with a computer system (or machine). When you programmed the buttons on the brain's screen, you gave users a way to interact with the Clawbot so they could make it stop or turn left or right. When you interact with a touchscreen on one of your devices (tablet, smartphone, smartwatch), those screens are often the only interface you have. Maybe your device has volume or power buttons as well but you mainly interact with the screen.
After programming your own buttons on the brain's screen, you should have a better sense of how a touchscreen might be programmed to detect which icon or button you want to select. Of course, there are more sophisticated ways of programming those features that professionals use instead of hard programming exactly where a button should be. Professional programs for GUIs are more adaptive to moving buttons and icons and other variables, but they share some of the same underlying principles.
Those principles form the foundation of the User Experience (UX) while using a UI. The User Experience is how well the interface lets me, as the user, do what I'm trying to do. Is the interface working as I expect it to? Is it responsive to what I'm trying to communicate with my presses? Is it organized well, or can buttons/icons/menus be moved around to make it easier? What does the interface look like in general? Is it pleasing to look at and does it make me want to use it more often? When a UI is still being developed and undergoing iterations, the developers collect data on what works as planned and what needs to be fixed or enhanced. That data then informs the next round of iterative design. Some of the UX changes recommended occur before the release of the device. But, the device might also be sold as is and those changes are made later before the next version is offered to the public consumer.