ajax - Why does Twitter use a hash and exclamation mark in URLs, and how do they rewrite search URLs?

Question

We understand the hash is for AJAX searches, but the exclamation mark? Anyone know?

Also, the "action" attribute for their search form points to "/search," but when you conduct a search, the hash exclamation mark appears in the URL. Are they simply redirecting from "/search" to "/#!/search"?

Note: the second part of the q remains unanswered: That is, are they redirecting the user from "/search" to "/#!/search", or do they send the user to "/search" and use JS on the page to rewrite the URL? – Crashalot Jan 26 at 23:51

Thanks!

Answer 1

It's become the de facto standard that Google has established to ensure consistency and make ajax urls crawlable.

See http://code.google.com/web/ajaxcrawling/docs/getting-started.html

I believe they are using history.pushState. You can do history.back() in the console and it'll lead you back to the page.