In all the history of computing, more files are dated January 1, 1980 than any other date in history. People must have been really busy that day. Then again, computers are not known for properly keeping time.

January 1, 1980 was not the first day of the 80s decade; 1980 was the last year of the 1970s decade, which is a concept that a majority of people still can’t understand.

On January 2, 1980 Jimmy Carter was still President of the United States. The top selling personal computer was the Apple II Plus. The Internet didn’t yet exist, but its predecessor the ARPAnet was around. Microsoft sold BASIC language interpreters and had just released its first operating system, XENIX, based on Unix. Facebook founder Mark Zuckerberg wasn’t even born yet.

The reason that more files feature the January 1, 1980 timestamp has nothing to do with that date. Nope, a more relevant date was August 12, 1981. That’s the date that the IBM PC was introduced. Its operating system was PC DOS 1.0. Unless you told it otherwise, PC DOS believed the current date to be Tuesday, January 1, 1980 and the time to be midnight.

Like all computers, the IBM PC featured an internal clock. What it lacked was a battery to backup the time when the computer was turned off. So every time you started an IBM PC or one of its innumerable clones, you were faced with two prompts, Date and Time. (The login prompt would still be about 15 years away.)

As you would expect, most people didn’t bother to input the date and time: It was far easier to whack the Enter key twice and start working than it was to type 9-27-83 and then 9:03.

Because few people typed in the proper date and time, their computer files were timestamped January 1, 1980. That meant you could never search for files based on their creation date, a problem that didn’t seem to bother many PC users back in the day.

Naturally, I was one of the few who actually bothered to type in the proper date and time. In fact, I had to manually issue the DATE and TIME commands every so often because the PC was terrible at keeping track of the time. But when I used someone else’s PC, especially to do troubleshooting, I’d see legions of files timestamped 01-01-80. It was insane!

After a spell, you could purchase a time card for your PC. That expansion card featured a tiny battery so that the computer could keep track of the time when it was turned off. Special startup software input the proper date and time automatically. It was a time-saver.

Eventually time cards were combined on all-in-one memory/printer/serial expansion cards. And then, finally, all that junk was included on the motherboard of all PCs.

Today, of course, not only do computers keep track of the time when they’re turned off, but they regularly communicate with the Internet’s atomic clocks. Properly time stamping files is no longer an issue. But it sure was 33 years ago when way too many files appeared to have been created on Tuesday, January 1, 1980.