In familiar with tmux, which is basically a fancy SCREEN replacement. It has its uses, though I prefer to work with byobu if it’s available.

All that being said, it doesn’t replace a terminal emulator (which the software that is running the window on your graphical desktop and knows how to draw text) – if you already have a terminal emulator then tmux allows you to do some fancy stuff with it – such as cramming a single window with multiple views. The multiple panes, BTW, never worked for me: I prefer a single full screen window for most things, not only terminal windows.