If you click a button or link and nothing happens for an unusually long time, your browser is "hanging" or "freezing" (they're the same). This means that it's either waiting for information from a server or busy processing internally.
At times, traffic on the Internet can be heavy, and you may have to wait a little bit longer for a response from our servers. It's not that the load on our servers is too great, but rather that the lines connecting our server with your computer are too busy. The Internet can sometimes experience bottlenecks and traffic jams, just as freeways do.
Delays caused by heavy traffic shouldn't last more than a few minutes. If one does, the best solution is usually to resubmit your request by clicking the same button or link again.
If your browser hangs or freezes frequently, it may help to clear your browser's cache.