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

# Classes

* [Helper Class](/xoops-modules-cookbook/core-classes/core/helper-class.md)
* [Other Key Classes](/xoops-modules-cookbook/core-classes/core/key-classes.md)
* [Criteria](https://github.com/XoopsDocs/xoops-modules-cookbook/tree/97c34b5a4588c5266ea433c7ad0eae3daccad339/en/book/core/Criteria.md)
* [XoopsObject](https://github.com/XoopsDocs/xoops-modules-cookbook/tree/97c34b5a4588c5266ea433c7ad0eae3daccad339/en/book/core/XoopsObject.md)
* [XoopsObjectAndHandler](https://github.com/XoopsDocs/xoops-modules-cookbook/tree/97c34b5a4588c5266ea433c7ad0eae3daccad339/en/book/core/XoopsObjectAndHandler.md)
* [XoopsObjectHandlXoopsPersistableObjectHandler](https://github.com/XoopsDocs/xoops-modules-cookbook/tree/97c34b5a4588c5266ea433c7ad0eae3daccad339/en/book/core/XoopsPersistableObjectHandler.md)