4×4 16 Key Matrix Membrane Switch Keypad Keyboard:

A Universal 4x4 16 Key Matrix Membrane Switch Keypad Keyboard is a type of input device commonly used in electronic projects, embedded systems, and various consumer electronics. Here's what each part of the name refers to:

1. Universal: This typically indicates that the keypad can be used with a variety of systems or microcontrollers. It suggests compatibility with different platforms or architectures.
2. 4x4: This refers to the arrangement of keys on the keypad. In this case, it means there are 4 columns and 4 rows of keys, resulting in a total of 16 keys.
3. Matrix: The keys in the keypad are arranged in a matrix formation, where each key is at the intersection of a row and a column. This arrangement allows for a large number of keys to be connected using a minimal number of pins on a microcontroller.
4. Membrane Switch: This indicates the type of technology used in the construction of the keypad. Membrane keypads consist of several layers, including a top membrane layer with the key labels, spacer layers, and a bottom membrane layer with conductive traces. Pressing a key causes the top and bottom membranes to connect, resulting in the activation of the corresponding electrical signal.
5. Keypad/Keyboard: These terms are often used interchangeably and simply refer to the input device used for entering data into a system by pressing keys.