# LXD > This is the documentation for LXD, a system container and virtual machine manager. 2014-2026 AGPL-3.0, LXD contributors ## Pages in this subsection - [Preseed YAML file fields](https://canonical.com/lxd/docs/default/reference/preseed_yaml_fields/index.html.md): You can configure a new LXD installation and reconfigure an existing installation with a preseed YAM... ## Optional - [Top-level llms.txt](https://canonical.com/lxd/docs/default/llms.txt): Complete documentation index.