What does “?ref=ts” mean in a Facebook application URL?

Question

When Facebook drives traffic to an application, it often append &ref=whatever to the query string. This is useful for figuring out which integration points

Answer 1

As noted, ref=ts is appended to the url whenever a user makes a search in the Top Search input field.

Also note that people tend to copy/paste links in their website and blogs, without trimming useless GET strings. So it is possible if you get a high number of referrers coming from the top search that they are in fact links that propagate outside of Facebook.