This may be an old joke, but it was new to me....

"There are 10 kinds of people in the world. Those that understand binary, and those that don't".

And checking it on the web, I see there are people quoting it who didn't really even get it...as in...

There are ten types of people on this world. Those that understand binary and those that don't.

Perhaps it depends on whether you read visually or sub-vocally....