Today, all of sudden, when I use Google to search, any documents found have the search words highlighted in diiferent colours.
What have I done to get this and more impotantly, how do I get rid of it because it is seriously irritating!

Not sure how you turn it on (or indeed off) but sounds like Google cache, this might point you in the right direction.

Thanks, Found it!! On the Google toolbar there is an icon that resembles the end of a wax crayon. Activate/disactivate highlighting of search words!!!!!!
That's better

They probably spent weeks developing that feature, there's thanks for you...