Expression Studio 4 Web Professional includes a complete set of professional design and development tools for creating modern standards-based Web sites, streaming video, and Web graphics. It includes three professional applications that work together: Expression Web, Expression Encoder, and Expression Design.
Microsoft Expression Web gives you the tools you need – PHP, HTML/XHTML, CSS, javascript, ASP.NET, ASP.NET AJAX, visual diagnostics, cross-browser debugging features & sophisticated CSS design capability – to produce high-quality, standards-based Web sites.