A video switcher is a device used in video production to select and switch between multiple video sources. It allows operators to control which video feed is displayed on a screen or recorded. This is essential for live broadcasts, events, and video editing, as it enables seamless transitions between different cameras, graphics, and pre-recorded clips. Video switchers can be hardware-based or software-based, with many modern options available for computers. They often include features like effects, transitions, and audio mixing capabilities. Popular brands include Blackmagic Design and Roland, which cater to various production needs and budgets.