> Show HN is for something you've made that other people can play with. HN users can try it out, give you feedback, and ask questions in the thread.

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> Off topic: blog posts, sign-up pages, newsletters, lists, and other reading material. Those can't be tried out, so can't be Show HNs. Make a regular submission instead.

Source: https://news.ycombinator.com/showhn.html