Stop the execution of a script

I have from time to time a message from Windows Internet Explorer as follows: "Stop the execution of this script? A script on this page this slows Internet Explorer. If it continues, your computer may stop responding. " So I answer "yes", but later or on another occasion, the message reappears. I do not lead off because I do not understand this. I count on the usual experts to guide me. (I do not even know what a "script", you really find me no. Thanks in advance

Why not use Opera or Firefox browser?

Much more powerful!

To begin ------- ---------------
Empty your browsing history
start
Panel
Internet option
Browsing History
remove

Thank you to you both, I think I'm out. But I still do not know what a "script" In the next time. New question: how to incorporate a picture as you are next to your nickname on the messages. Answer point by point detail please because I do not juggle with my pc