In terms of jQuery (or Javascript), what happens behind the scenes when a person posts a comment on Facebook, Twitter, or a blog? For instance, do they sanitize the text first, and then pattern match URL's into an actual link? Are there other items of concern that the client-side should check in addition to doing some checks on the backend? I have found a few regex's for turning URL's into links, but I'm not sure if there are better solutions. I'm trying to wrap my head around the problem, but I'm having a difficult time knowing where to start. Any guidance you can provide is greatly appreciated!