> For the complete documentation index, see [llms.txt](https://fig.gitbook.io/fig/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://fig.gitbook.io/fig/apps/key-concepts.md).

# Key Concepts

- [Running Shell Commands](https://fig.gitbook.io/fig/apps/key-concepts/running-shell-commands.md)
- [Reading Environment Variables](https://fig.gitbook.io/fig/apps/key-concepts/reading-environment-variables.md)
- [Accessing Files & Saving Data](https://fig.gitbook.io/fig/apps/key-concepts/saving-data.md)
- [Loading Local Resources](https://fig.gitbook.io/fig/apps/key-concepts/loading-local-resources.md)