# GNU Screen
GNU Screen is the **original terminal multiplexer** (1987) — it invented the category: detachable sessions, multiple windows in one terminal, processes that survive a dropped connection. Every [[Terminal Multiplexers|multiplexer]] since is a response to it.
For interactive daily use it has been superseded by [[TMux]] (cleaner client-server model, saner scripting, active plugin ecosystem, panes that arrived decades earlier). Development continues, but slowly, and its large legacy C codebase showed its age when a 2025 SUSE security audit turned up multiple vulnerabilities in the 5.0 release.
## Why it still earns a place
- **It's already there.** Preinstalled or one package away on effectively every Unix since the 90s — ancient servers, appliances, BSDs, minimal rescue environments where tmux isn't available
- **Serial consoles.** `screen /dev/ttyUSB0 115200` remains the fastest way to talk to a router, switch, or embedded board over serial — the niche where screen is still the default answer
- Muscle memory: `Ctrl-a` workflows from a generation of sysadmins
Know it exists, know `Ctrl-a d` detaches and `screen -r` reattaches, reach for [[TMux]] or [[Zellij]] for everything else.
## References
- https://www.gnu.org/software/screen/
## Related
- [[Terminal Multiplexers]] — the category it created
- [[TMux]] — its successor in practice
- [[Byobu]] — friendly frontend that can drive screen or tmux