What is a BCD file?

I grabbed a ZIP file from Bugzilla and once I unzipped it, I ended up with this weird BCD file (like, something like: xxxxx.dvd.bcd)
Those two things are tripping me up. I guess the extension is just .bcd? I did some digging online and saw some mentions of Windows Vista, but I don't really get it.

Does anyone actually know what's going on here? It’s kind of annoying when they release stuff in formats that nobody has ever heard of.

Thanks in advance

CLICK 👍

What if it looks more like this:

http://filext.com/file-extension/BCD

.

BugzillaCD