Byobu is a terminal multiplexer that allows users to manage multiple terminal sessions within a single window. It enables users to create, detach, and reattach to sessions, making it easier to work on different tasks simultaneously without losing progress. Originally developed for the GNU Screen and tmux environments, Byobu enhances the user experience by providing a more user-friendly interface and additional features like status notifications and easy session management. It is particularly useful for system administrators and developers who need to maintain persistent sessions on remote servers.