In the case of the MacBook this means a display of 2880×1800 pixels, more than twice as many dots as a 50in high-definition television.
Squeezed down into a 15in screen this means everything looks pin-sharp, as clear as a printed page and much more vibrant thanks to the bright, LED-backlit display.
At the launch event Apple highlighted the benefits of this extra resolution by showing a high-definition movie playing at full size in just one corner of the screen.
A common problem with earlier high-resolution computer screens was that they made everything tiny – more dots squeezed into the same space meant everything became proportionally smaller, making text and icons uncomfortably minute.
Apple engineers have side-stepped that problem by automatically doubling the size of everything on screen. And since the new model sports a display with exactly twice as many dots in each direction, the result is a display that is indistinguishable from the previous version except it's much sharper.
While the screen is a marked improvement for consuming content, it doesn't improve the process of editing.
Ironically, with pixels smaller than the eye can see it's actually more difficult to check the detail of photos or videos on the MacBook's ultra-sharp screen. The only way is to zoom in past 100% magnification which, to my mind, defeats the purpose of a Retina display.
Web browsing is a bit of a mixed bag. While text appears incredibly sharp on the high-res screen, the Mac's trick of double-sizing everything makes logos and artwork appear mushy – less clear than they are on a bargain basement laptop. That situation won't last; such is the influence of Apple that most designers will update their sites to take advantage of the improved display.
Battery life on the Retina model is slightly disappointing too. While most Mac laptops get very close to their claimed seven-hour battery life, many owners of the Retina model are reporting running times of around half that, even when performing fairly mundane tasks like web browsing.
This machine offers the ultimate in quality with a price-tag to match. It's arguably the perfect laptop for mobile workers who need a top-notch display on the move. Users who spend more time at home, especially those who edit photos or videos, might be better served by the equivalent standard MacBook Pro, investing some of the £300 saving in a larger second monitor like the 24in Asus ProArt reviewed here in January.
Apple MacBook Pro with Retina display from £1799
Positives: Incredible screen and fast processor in a surprisingly thin shell.
Negatives: Makes websites look mushy; poor battery life.