It's a legacy thing.
https://en.wikipedia.org/wiki/HTML_ComponentsIt's only in IE as far as I know, and it's really just there in case you need it for an older application that uses HTC components. I've never come across the need to use it. I would also be curious about how to recognize when it's possible to use it or some example websites that use HTC Components.
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Dave Morris
3Ci @ Southern Company
Atlanta, GA
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Dave Morris, 3Ci at Southern Company