User interface between man and machine

The user interface serves as a mediator between man and machine. The machine can only do something with concrete instructions, while we tend to think in abstract terms. Machine language and natural language are very different. A user interface is needed to mediate between machine and human.

In software, the user interface often means the graphical user interface of the application. Results and functions of programmes are displayed graphically so that users can work as easily as possible. By pressing a key or clicking a button, a certain function can be executed without the users knowing what is actually happening in the background or what information is used by the programme to calculate from inputs and databases. The machine in turn returns the result graphically. The commands and navigation are realised via individual keys. The command line itself is its own kind of interfacace.

One way to communicate with software or hardware is to press a button or click the mouse. Nowadays, many applications can be controlled by speech. User interfaces can also work with different input and output methods at the same time. The speech recognition of a smartphone could convert spoken words into text and show it on a display.

The way in which functions and information are made available through the user interface determines what the user thinks about the usefulness of the software. Cluttered graphical interfaces can confuse and frustrate users, even if the program is elegant and powerful.

Such programs offer poor user experiences and are evaluated negatively, even though they could fulfill all the functions needed. The interface between software and humans has practically failed. Sufficient planning and time must therefore be invested in the user interface. One must be aware of the target group as well as take into account their prior knowledge.