This will work in all IE browsers below IE 7 but NOT IE 7 itself.

This will work in most browsers (Firefox 2 and 1.5, IE 7 and 6, Opera) however it is not recognised in IE 5.5 and 5.

This works in all versions of IE but not other browsers.

This will work in IE 6 only.

This will work in IE 7 and 6.

This will only target IE 7.