An HDMI switch is a device that allows multiple HDMI sources, like a Blu-ray player, gaming console, or streaming device, to connect to a single HDMI input on a TV or monitor. This is useful when you have limited HDMI ports on your display and want to easily switch between different devices without constantly plugging and unplugging cables. Most HDMI switches come with a button or remote control to select which source you want to view. They support high-definition video and audio, making them ideal for home entertainment systems. Some models even offer features like 4K support and HDCP compliance for enhanced performance.