Compound Document Format (CDF) is a set of W3C candidate standards describing electronic compound document file formats that contains multiple formats, such as SVG, XHTML, SMIL and XForms. The core standards are the Web Integration Compound Document and the Compound Document by Reference Framework (CDR). As of August 19, 2010, the Compound Document Format working group has been closed, and W3C's development of the standard discontinued.