I disagree, I hate car analogies, but here goes:
I know how to use my car, I can change the wheels, oil, filters, diagnose basic problems that sort of thing. The likes of Jeremy Clarkson freely admit to knowing sod all about their cars, other than how the controls work, but he knows how to use a car in a far more skilled manner than I.
Likewise one doesn't need to know how to program to use a computer, in order to be able to use it. In fact that's probably a good thing, because it's democratising, there are now systems which enable spreadsheet jockies to hook up their spreadsheet to an HPC cluster, it's not programming, but it's still al very powerful tool.