Well, you might be thinking, “hey, I can just open up multiple terminal windows or open
up multiple tabs in my terminal application, so why would I ever need to use Tmux?”

The power of Tmux is that you can detach, or leave, or exit tmux, while all those terminal
sessions that are managed by Tmux are still running in the background. Then you can come back at a later time and reattach to those terminal sessions. If you work on remote systems, then Tmux can be a lifesaver.