Computer hardware devices include webcams, scanners, mice, speakers, trackballs, and light pens. Webcams connect via USB or network and are used for video calls and conferencing. Scanners optically scan images and documents into digital formats. Mice are pointing devices that detect motion to move a cursor. Speakers have internal amplifiers and audio jacks. Trackballs contain ball and sensors to detect rotation for cursor movement. Light pens allow pointing directly on CRT displays.