Filter Support IE4 introduced visual and transition filters. Transition filters, can be either the Blend Transition , or one of the many Reveal Transitions . The Fader script uses the Blend Transition . The Reveal Transitions have been discussed at great length in Column 19 .
Filters are environment-specific.
They are supported only on Windows and some Unix platforms. On Unix, filters are available to IE5. The browser used is IE4.x for Windows, running in Compatibility Mode. Although not widely publisized, it is possible to install both IE4 and IE5 on the same system. Filter support is determined by an entry in your system's registry.