These include the ` behavior ' CSS property , which connects the HTML elements with JScript behaviors ( known as HTML Components , HTC ) ; HTML+TIME profile , which adds timing and media synchronization support to HTML documents ( similar to the W3C XHTML+SMIL ) ; and the VML vector graphics file format . These include the ` behavior ' CSS property , which connects the HTML elements with JScript behaviors ( known as HTML Components , HTC ) ; HTML+TIME profile , which adds timing and media synchronization support to HTML documents ( similar to the W3C XHTML+SMIL ) , and the VML vector graphics file format .