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

# FUNDAMENTALS

- [Convert Postman Collection to OpenAPI Yaml](https://docs.api.market/fundamentals/convert-postman-collection-to-openapi-yaml.md): If you have never converted Postman Collection to OpenAPI Yaml before it can be a bit daunting task. Just follow the below simple steps to convert.
- [Create OpenAPI spec using ChatGPT](https://docs.api.market/fundamentals/create-openapi-spec-using-chatgpt.md): If you have never worked with OpenAPI spec then creating one can look like a daunting task but it is actually very easy. You can auto-generate an OpenAPI YAML using ChatGPT. Just Follow this tutorial.