In the comments on StackOverflow, <http://en.wikipedia.org/wiki/Inotify> was misparsed to include the trailing angle bracket. Also there was a semi-colon after it for some reason. **See my comment below for an example.** In [RFC 3986 Appendix C. Delimiting a URI in Context][1], three ways are suggested to indicate that a bit of text is a URL. 1. Angle brackets like `<http://en.wikipedia.org/wiki/Inotify>` 2. Quotes like `"http://en.wikipedia.org/wiki/Inotify"` 3. Whitespace like `http://en.wikipedia.org/wiki/Inotify` Angle brackets are "especially recommended" in the RFC. Markdown syntax also [automatically links angle brackets][2] and SO's [editing help mentions it][3]. The [comment formatting help][4] doesn't say comments auto-link differently. Comments do auto-link, why do it different? Thanks for looking. I know free-form URL parsing is a pain, I maintain a library myself. UPDATE: As you can see in this example -- <http://en.wikipedia.org/wiki/Inotify> -- the posting grammar knows how to deal with URLs in angle brackets. Why not in comments? They both do auto-linking. Unless there's some other benefit to the user they should do them the same to avoid confusion. This allows users to learn just ONE set of quirks, not two. [1]: http://tools.ietf.org/html/rfc3986 [2]: http://daringfireball.net/projects/markdown/syntax#autolink [3]: https://meta.stackoverflow.com/editing-help#bare-urls [4]: https://meta.stackoverflow.com/editing-help#comment-formatting