Dan Lewis runs the popular daily newsletter Now I Know (“Learn Something New Every Day, By Email”). To subscribe to his daily email, click here.

If you used a Mac before it became super-popular to do so, you probably know a certain sound very well. The sound —a short burst, a mix between a bell and a steam train’s whistle—would ring whenever you did something you weren’t supposed to. Hit the delete key too many times, thereby deleting nothing? Beep. Click where you couldn’t? Chirp. 

Have no idea what I’m talking about? You can listen to the sound by clicking here. And when you click, pay attention to the file name. It’s not Beep.wav or Chirp.wav or even Toot.wav. It’s Sosumi.wav, and “sosumi” isn’t typically the name of a sound. It’s vaguely legalese, even—intentionally so, it turns out.

Apple Computer was founded in 1974. Apple Corps, the holding company for the Beatles (and owner of the Beatles’ record label, Apple Records), was founded in 1968. The latter wasn’t too happy about the former’s decision to use the “Apple” name, so out came the lawyers. The Beatles sued in 1978, and a few years later, the two parties settled. Apple Computer paid $80,000 to Apple Corps, Apple Corps agreed to stay out of the computer business, and Apple Computer agreed to stay out of the music business. (Apple Computer’s decision to start iTunes sparked a follow-up lawsuit, which Apple Computer won.)

For much of the 1980s and 1990s, Apple Computer’s lawyers were hawkish about accidentally making music—they didn’t want the company to violate the terms of the agreement. When Apple Computer created a new operating system (“System 7″) for its Macs in 1991, the question came up again. A guy named Jim Reekes was the lead engineer for the Apple Sound Manager for System 7, and he and his team were creating all sorts of different noises. Sounds needed names so that the operating system could find them and play them when appropriate (and so users could customize their sound profiles), so Reekes and team went to work giving each sound a moniker. Sosumi, originally, was called “Chime.”

The lawyers said no. “Chime” was something one would call music, and Apple Computer wasn’t supposed to make music. Reekes jokingly replied that he’d rename the sound “Let it Beep,” a reference to 1970’s Beatles song “Let it Be,” but apparently, not everyone got the joke. That, as he told Boing Boing via email, gave Reekes a great idea:

As everyone was laughing, someone even took me seriously and said I could never get away with that! I said, “so sue me” and that’s when I realized my scheme. I told Sheila [Brady, who put together the System 7 disks] the new name would be spelled “s-o-s-u-m-i”. I asked she return the message to legal, but not to use voicemail (since she’d have to pronounce it) and instead send an email with some story about it being Japanese and not meaning anything musical. (So I don’t know what she actually told them).

Apple Computer’s legal team approved the name, and the Beatles never seemed to object.

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