FHTML (Fluid Hyper Text Markup Language) or FluidHtml is an interpreted markup language that renders in Adobe Flash.Rich Internet applications are globally popular, but most are not easy to learn, and generate pages that are not amenable to search engine optimization; FHTML was created to deal with these issues. FHTML can be used with server-side web technologies such as Java, .NET Framework and PHP, and includes a layout engine that is more flexible than CSS. FHTML is compatible in all major web browsers, and allows web developers to create rich web functionality using easy HTML-like code. Development of the language is currently in private beta testing, but is planned to be opened for beta testing sometime in 2010.

FHTML has the ease of use and search engine optimization of HTML, and does not need to be compiled like Flex, Silverlight, and Flash.Websites and schools can use the technology for free without support. FHTML runs on 95% of current browsers with no additional plug-ins or download required. It supports 3D computer animation natively, and reduces total cost of ownership for a business..NET, Python, Java, PHP, and Ruby developers can all write FHTML in their original language.