One obvious reason why Steve Jobs’s latest medical leave is so troubling to Apple fans and investors is that Jobs, unlike most CEOs, has proven as adept at design and R&D as he has at corner-office despotism. But among the long list of Apple products to debut under Jobs, one invention has gone largely without remark: the Apple logo itself.

In its 35-year history, Apple has had only three corporate badges. Two of them—variations on the iconic apple with the single leaf and bite mark—wouldn’t have existed were it not for Jobs.

When Apple Computer debuted in 1976, co-founder Ronald Wayne designed the first logo (larger version here), which resembled a Jethro Tull album cover—a woodcut of Sir Isaac Newton, with an apple dangling over his head and the tagline: “A mind forever voyaging through strange seas of thought … alone.” (Sound like freshman poetry? It’s actually Wordsworth.) Jobs reportedly thought the logo was too arcane—the man was undoubtedly right—and he scrapped the medieval oddity in 1977.

The logo job then fell to designer Rob Janoff, who would give the House of Jobs its prettiest present: the famous “rainbow apple.” While the bite mark was supposedly a reflection of Apple’s tagline at the time (“Byte into an Apple”), Janoff would say in a later interview that his primary aim was to “prevent the apple from looking like a cherry tomato.” But it was Jobs, at least according to Apple-fan lore, who jiggered with the logo’s chromatic order so that green would be at the top—which made sense, because that’s where the leaf was.

The rainbow apple stuck around for 22 years—until Jobs’s return to the company in 1997. Part of his overhaul included sending the logo back to the shop in 1998. (A rainbow badge on the sleek new iMacs, as tech geeks aplenty have pointed out, would have looked preposterous.) But Jobs had the sense to keep the apple silhouette. It had become almost as recognizable as McDonald’s Golden Arches. The millennial apple logo has since been rolled out in a variety of sizes and colors—most effectively, as a glowing shield on the Macbook laptops.

The jury might be out on whether Tim Cook is CEO material, but here’s one good bet: Designer Jonathan Ive—the man responsible for the sleek, industrial look of the company’s products—probably won’t be messing with Mr. Jobs’s apple.