Asciinema

A lightweight, text-based terminal recorder that captures shell sessions as shareable, copy-pasteable JSON animations.

Asciinema replaces bulky video files with efficient terminal recordings (casts) that treat stdout as data rather than pixels. Users record sessions via a Python-based CLI (pip install asciinema) to generate high-fidelity replays where viewers can select and copy code directly from the player. The platform hosts millions of recordings, serving as a standard for documentation and open-source demos by keeping file sizes minimal and text perfectly crisp at any zoom level.

https://asciinema.org