Affordance

Let's discuss a fundamental design concept called affordance as it can yield answers to the various questions that we had. Affordance means how an object and its properties are perceived by its design. Here it provides a clue about its operation:

The preceding diagram helps us to understand what affordance is in the design world that we're talking about; among the switches that we see, the first one represents a swivel operation, and another indicates an upward and downward operation. So, by merely seeing those objects, we can perceive what it supports and how. In the case of API design, affordance undoubtedly plays a crucial role, and it is an essential aspect of our API designs.