What is knob?

A knob is a small, often round handle used to operate a machine, door, drawer, etc. It is typically made of metal, plastic, or wood, and is attached to a shaft that rotates to adjust the function of the equipment. Knobs can come in a wide variety of shapes, sizes, and designs, ranging from simple and functional to ornate and decorative. They are commonly used in homes, offices, and industrial settings to help control and adjust various devices. Some examples of common types of knobs include door knobs, cabinet knobs, and control knobs for electronic equipment.