Keypads are input devices that combine multiple keys into a single interface for entering numbers, commands, or navigation inputs. They are commonly used in embedded systems, access control units, vending machines, and custom control panels.
These matrix and membrane keypads come in different formats such as 3×4, 4×4, and linear layouts. They are designed for easy integration with microcontrollers like Arduino, Raspberry Pi, and ESP32 using standard matrix scanning techniques.
Keypads offer a compact and structured way to handle user input when single-button controls are not sufficient.