Order of invention is important in some fairly subtle ways. We take for granted everything that exists as new technologies are introduced, but a few disruptions in this seemingly obvious order, and we'd all be leading very different lives.

The modern ballpoint pen became commercially viable around 1940. Ten years later, the first modern credit card, Diner's Club, gained consumer traction.

Thank goodness things happened in that order. I can only imagine the hilarity that would ensue today if waiters at restaurants had to bring a fountain pen and ink reservoir to the table after dinner just to sign the check.