Same origin policy : Because of cross domain policies browsers enforce your script execution may fail unexpectedly and without adequate error messaging.
The first argument passed to the callback function will be used as the script’s result.Also,the default timeout for a script to be executed is 0ms.Most of all, one must set the script timeout beforehand to a sufficiently large value.
Performing a sleep in the browser under test.
AJAX request is usually sent using XMLHttpRequest and wait for the ready state for the callback.
We will discuss about AJAX in later post.