# Reel

> reel is the Go library steep records through. It emulates a terminal, logs everything that happens to it in a timeline saved as asciicast, and exports timelines to GIF, MP4, WebM, WebP, PNG, screen text, and JSON, through a renderer and effects such as key overlays, zooms, highlights, and redaction.

This is one section of the documentation for steep, reel, and the reel CLI. [The overview](https://getsteep.dev/llms.txt) says which to use.

## Start here

- [Introduction](https://getsteep.dev/reel.md): What reel does, how to install it, and when to use it rather than steep or the CLI.
- [Your first recording](https://getsteep.dev/reel/first-recording.md): Run a command in a session, drive it, and export a GIF and a cast.

## Recording

- [Sessions and commands](https://getsteep.dev/reel/sessions.md): Open a terminal, run a command in it, send input, wait for the screen, and replay recordings.
- [Inspecting recordings](https://getsteep.dev/reel/inspecting.md): The inspector, the annotations in a recording, and stepping through one in Go.

## Exporting

- [Exporting](https://getsteep.dev/reel/exporting.md): Turn a timeline into files, cut it, take stills, and export a recording again later.
- [Output formats](https://getsteep.dev/reel/formats.md): Every format reel writes, how big each is, and the options it takes.
- [Export cookbook](https://getsteep.dev/reel/cookbook.md): Common exports, in Go, in a steep test, and with the CLI.
- [Rendering](https://getsteep.dev/reel/rendering.md): The window around a recording, its colors and fonts, and the terminal indicators it can draw.

## Effects

- [Effects](https://getsteep.dev/reel/effects.md): What effects are, the order they run in, how to aim one, and each one built in.
- [Redact](https://getsteep.dev/reel/redact.md): Hide secrets from a recording, what that covers, and where it stops.
- [Custom effects](https://getsteep.dev/reel/custom-effects.md): Write your own effect, and the interfaces that let it work with the rest.

## Help

- [Troubleshooting](https://getsteep.dev/reel/troubleshooting.md): Problems exporting and recording, and what causes them.

## Reference

- [How it works](https://getsteep.dev/reel/how-it-works.md): How a session becomes files, the event log behind every recording, and exporting compared with recording live.
- [Terminal features](https://getsteep.dev/reel/terminal-features.md): Every OSC, CSI, DEC, DCS, and APC sequence reel tracks, what it does with each one, and the exact Go name that exposes it.

## Optional

- [API reference](https://pkg.go.dev/getsteep.dev/steep/reel): every package, type, and function
- [Everything](https://getsteep.dev/llms-full.txt): every page of the site, as one file