It's not a dumb question. Don't worry about it. A lot of things can get confusing when you're starting out.
A double bounce is simply two separate strokes with one hand. You have to hit the first one before you can hit the second one so it doesn't really matter whether or not the second hit is considered a stroke or a bounce. I mention this because some teachers teach a double stroke roll as a stroke and a bounce. This can then confuse students when they hear the phrase "double bounce".
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