# Future topics

There are still a few topics that should be covered. Here are some of them, together with helpful resources.

* 🎥**Video:** [Immutable Relational Data](https://www.youtube.com/watch?v=28OdemxhfbU)
* 👥**Thread:** [Handling Errors](https://www.reddit.com/r/elm/comments/aj9pem/noob_question_the_elm_way/)
* 👥**Thread:** [MapN Problem](https://www.reddit.com/r/elm/comments/aqjkha/combining_the_errors_and_values_of_results_kind/)
* 👥**Thread:** [Keyed HTML](https://www.reddit.com/r/elm/comments/bsi6zd/img_src_reuse_issue/)
* 👥**Thread:** [How to model an application?](https://korban.net/posts/elm/2018-10-12-elm-guide-missing-part-url-handling-browser.application/)
* 👥**Thread:** [Error Handling](https://discourse.elm-lang.org/t/error-handling-in-elm/5086)