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I have a website that I am trying to convert educational videos from .mp4 format into a format that can be viewed on most browsers (explorer, firefox, chrome, and safari) as well as on mobile devices. Right now at [login to view URL] I cannot play these videos in Safari at present and this is unacceptable to my apple customers. I am using yahoo sitebuilder as my program to create and design and I would like to keep it.