What does this mean?

[Perdita Durango]

When I go on Facebook (and sometimes in other applications)
a box comes up saying "Internet Explorer Script Error" and asks if i want to keep running the scripts.
It doesn't seem to make any difference if I say yes, no or just close the box. (I usually just end up clicking the cross until it eventually goes away)

What on earth does this mean?
And what is a script anyway?

Does it have anything to do with why I can't send messages and other things on my facebook account? (my kids can access their Bebo and Myspace properly)

Thank you