Above is the logo of HTML5. It is available under Creative Commons 3.0 and was developed by Ocupop.
The purpose
According to W3C, “We intend for it to be an all-purpose banner for HTML5, CSS, SVG, WOFF, and other technologies that constitute an open web platform. The logo does not have a specific meaning; it is not meant to imply conformance or validity, for example. The logo represents “the Web platform” in a very general sense.”
Why orange in color?
Ocupop has a cool explanation for this.
“Orange is a very hot, fast, and striking color, but not nearly as intimidating or aggressive as red. Orange implies excitement, yet with undertones of caution. Orange grabs your attention, but doesn’t scream for it. In Chinese color theory, orange is the color of organization. In medieval heraldry, orange was symbolic of strength and endurance. Sexy with a safety net, organized, powerful and lasting. HTML5, this logo, and orange go quite well together.”
You can download HTML5 logos at W3.org