This is a big one. Most online purchases today are made via credit cards, but in the 1920s and ’30s, when the first precursors to credit cards appeared, the Internet hadn’t yet been conceived. Credit cards were never supposed to be used online and are insecure. Online forms require you to enter all your secret information (the credit card number, expiry date, and CSV number) into a web form. It’s hard to think of a less secure way to do online business. This is why credit card numbers keep being stolen.