When is a tablet not a tablet? When it's a PC.
According to U.K.-based research firm Canalys, tablets are PCs by another name, or even in sheep's clothing.
The argument isn't just semantics. If the number of iPads Apple sold in the fourth quarter of 2010 is added to the number of Macs sold during the same period, Apple vaults onto the Top 5 list of the world's biggest computer makers.
In fact, iPad sales pushed Apple to the No. 3 spot, said Canalys, with 11.5 million machines, or 10.8% of the global market. Only Hewlett-Packard, which sold 18.7 million systems, and Acer, with sales of 13.6 million PCs, led Apple last quarter.
According to Apple's latest earnings report , it sold 7.33 million iPads and 4.13 million Macs -- both records -- for a total of 11.46 million.
Tim Coulling, a Canalys analyst, argued for putting the iPad in the PC category, while a colleague criticized anyone who disagreed as "out of sync."
"It all has to do with how the tablet product is used," said Coulling. "It's a multi-use product that carries out such functions as word processing, e-mail and the Internet."
To back up his argument, Coulling said tablets were analogous to netbooks, and said that the same debate -- "Is it a PC?" -- raged several years ago. "It's the same thing we saw with netbooks," he said. "People said, 'This isn't a PC, we can't do everything we want to, we can't burn a DVD, it doesn't have a fast processor.
"But when new products come along, attitudes have to change," Coulling said. "You have to look at what new developments are taking place in the market."
Other research companies, however, disagree.
Neither of the biggest U.S. research companies, Gartner and IDC, count tablets as PCs when they estimate sales numbers.
"We see PCs as devices meant to run a general purpose operating system that allows content creation as well as content consumption," said Jay Chou, an analyst at IDC.
Apple's iPad runs iOS, the same mobile operating system that powers the iPhone smartphone. The two also share the App Store, Apple's software marketplace, and the iPad can even run iPhone applications.
"For now, we're not counting tablets as PCs, even though they are cannibalizing PC sales to some extent," added Chou. "But that's not set in stone."
Chou did acknowledge that IDC counts slate- and tablet-style devices which run Windows in its PC sales figures, however.
If IDC had done the same for iPads, it would have had to rank Apple as the world's second-largest seller of PCs, lagging only HP's estimated 17.96 million machines for the quarter.
Other research firms' refusal to count tablets as PCs rubbed Canalys the wrong way.
"Any argument that a pad is not a PC is simply out of sync," said Daryl Chiam, another Canalys analyst, in a statement released today. Tablets like the iPad, Chiam added, "compete for the same customers [with netbooks] and will happily coexist."
Like Coulling, Chiam also referenced previous market shifts to bolster Canalys's case. "Apple is benefiting from pads, just as Acer, Samsung and ASUS previously did with netbooks," he said. "The PC industry has always evolved this way, starting when Toshiba and Compaq rode high on the original notebook wave."
Chou countered, again citing tablet OSes as the deciding criteria but also bringing into the debate Apple's own positioning of its iPad.
"Tablet apps are not full-fledged programs like the ones we run on the PC," Chou argued. "And Apple has created a very distinct usage model [for the iPad] that it can sell to customers."
Apple certainly doesn't consider the iPad just another computer: When CEO Steve Jobs launched the iPad a year ago, he famously called it "magical" and "revolutionary," words he doesn't use when introducing a new Mac.
Nor does Apple add iPad sales to the Mac category when it publishes sales figures each quarter.
IDC's Chou took Apple's side. "Media tablet OSes may evolve into something different than smartphone OSes, but at the moment, they're just enlarged cell phones in many senses."
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