Who Add “_” Single Underscore Query Parameter?

Question

I have a PHP server running on Apache, I get lots of request looks like this,

10.1.1.211 - - [02/Sep/2010:16:14:31 -0400] \"GET /request?_=1283458471913&         


        

Answer 1

jQuery adds a parameter like that to get around IE's caching.

edit: it only adds it for get requests, and only if the option cache is false:

cache: false