Last fall Apple fired executive Scott Forstall, considered by many to be a Steve Jobs protégé. His departure prompted a flurry of discussion about a formerly obscure design-industry concept that he had championed: “skeuomorphism.”

In the physical world, a skeuomorph is an ornamental version of something that was, in an earlier product, a functional necessity. Fake shutter sounds in digital cameras. Fake candles in electric chandeliers. Fake grain in leatherette.

In software, skeuomorphs are everywhere. Desktop folders look like physical filing folders, the Trash can looks like a wastepaper basket and the Save button looks like a floppy disk.

Those shapes don't serve any technological function. But there is, of course, a human reason for software skeuomorphs. In the 1980s, to help the public make the transition to computers, Apple and Microsoft designers chose real-world shapes for on-screen icons to convey their meanings. Jobs, in particular, was a fan of skeuomorphic designs. And in the beginning, they played a big role in helping the graphic user interface catch on.

These days there's a building backlash to skeuomorphic design—a rising sense that Apple has gone too far.

When you turn a page in an Apple e-book, the “paper” curls as you flip it over, even revealing the faint image of words printed on the other side. Apple's Contacts app looks like a physical address book, complete with fake “staples” in the “binding” between “pages.” The background screen of its Game Center app is made to look like green felt, as on a Vegas gaming table. And, perhaps most superfluous of all, torn-off paper scraps adorn the top of the Calendar program's “binding,” as though previous months' pages have been torn away.

These design features, critics argue, no longer help novices make a transition. You don't need unsightly paper remnants to understand that you are using a calendar. A curling-page animation just slows the reader down for the sake of showing off. Meanwhile slavish dependence on real-world visual metaphors could be holding back more creative, space-efficient or self-explanatory designs.

Sometimes Apple uses skeuomorphs that would not even make sense to modern-day customers. How many members of Generation Y have ever even used a Rolodex? In Apple's new Podcast app for the iPhone, the dominant visual element is a reel-to-reel tape—a technology that fell out of use 30 years ago.

Microsoft's latest operating systems—Windows Phone, for example—run full bore the opposite direction. Their interfaces are all digital, with no references to the physical world. The designers are clearly saying, “It's 2013, people. We don't need fake wood grain and green felt to convey software functions.”

Many Apple designers would probably argue that helping novices recognize software functionality isn't the sole objective. They would probably point out that detailed photorealistic depictions of physical things also look cool. Yes, it's showing off, but it's part of making something pleasant to use. In truth, many of the complaints come from other designers. You don't hear the masses—people who are actually buying these products—griping about those little digital staples.

In any case, Apple's famous chief of hardware design, Jony Ive, is now in charge of software design as well, and he's not a fan of skeuomorphism in software. The days of iPhone apps that have fake wood grain, fake brushed metal and fake stitching in fake leather are probably numbered.

And that's fine. Skeuomorphism in software has its place when used well: it can put you at ease with a new program in a flash and convey functions with simple visual metaphors (camera apps will always have camera icons). As with any design concept, this one can be taken too far. The instant a skeuomorph makes software less pleasant to use, somebody should rein it in.

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