A TouchEvent is a type of event in web development that occurs when a user interacts with a touchscreen device. It captures the user's touch actions, such as tapping, swiping, or pinching, allowing developers to create responsive and interactive applications. Touch events are essential for mobile devices, where traditional mouse events may not apply. There are several types of touch events, including touchstart, touchmove, and touchend. The touchstart event triggers when a finger touches the screen, while touchmove occurs as the finger moves across the surface. Finally, touchend signals when the finger lifts off the screen, enabling developers to respond to user gestures effectively.