> For the complete documentation index, see [llms.txt](https://help.iodd.kr/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.iodd.kr/appendix.md).

# Appendix

- [Legacy Device & Historical Reference](https://help.iodd.kr/appendix/appendix.md): Legacy IODD device reference, company history, patents, older model details, emergency recovery procedures, and support notes.