Customers might not like the idea of technology that allows some uses of music (like copying iTunes downloads to their iPods) but forbids others (like copying the same song to another kind of music player). But until recently, it didn't seem to bother the executives behind these anti-piracy systems.

They all agreed that anybody selling downloadable music and movies needed to police what customers did with their purchases.

Last week, however, the person responsible for the most successful copy-control software in the music market, Apple chief executive Steve Jobs, ruffled feathers with the question: Do we need any of this in the first place?

In an essay called "Thoughts on Digital Music" on Apple's site, Jobs wrote that his company's iTunes Store used copy-control software called FairPlay only because major record labels insisted on it. Those same labels' demands made it impossible for Apple to share its technology, he said. So his proposed solution to the "this download will only play on my iPod" problem is to abolish copy-control software altogether.

Since that remarkably blunt piece of writing hit the Web, the debate over whether technology can curb illegal file sharing has come back to life. That's good. But in the process, a lot of old myths are resurfacing -- and believing them will stop you from understand the deeper problems with the digital-media market. The myths include:

· "Apple can't share FairPlay with other companies, because the technology could get leaked and eventually prompt the labels to pull their catalogues from the iTunes store."

That's not necessarily so.

You can't completely dismiss Apple's contention; only Apple knows the fine print of its deals with the record labels. We don't. But the simple way Apple's copy-control system works should make it relatively easy for outsiders to join the FairPlay game.

FairPlay assigns the police work to the iTunes program on your Mac or PC, not the iPod. As a result, you can plug a friend's iPod into your computer and copy your iTunes purchases to it, even if that iPod is already loaded with your pal's iTunes downloads.

Plus, Apple has already taken a baby step toward putting FairPlay in other companies' hardware, in the form of Motorola cellphones that include a miniaturized version of iTunes. If the iTunes Store survived that experiment, it should be able to live through the addition of FairPlay compatibility to other playback-only devices, such as handheld organizers or car stereos.

It would be different if Apple were to let somebody design a competitor to iTunes. A lot more would be at stake in that case.