iMac (Mid-2007 or later)
MacBook (13-inch Aluminium, Late 2008), (13-inch, Early 2009 or later)
MacBook Pro (13-inch, Mid-2009 or later), (15-inch, Mid/Late 2007 or later), (17-inch, Late 2007 or later)
MacBook Air (Late 2008 or later)
Mac Mini (Early 2009 or later)
Mac Pro (Early 2008 or later)
Xserve (Early 2009)
While these Macs were classed as supported, they didn't support every new feature of Yosemite. There were a number of the Continuity features, which enabled better communication between iPhone, iPad and Mac, that didn't work on older Macs due to lacking newer Bluetooth support.
Will OS X 10.11 have a new look? OS X 10.11 interface & design
Given that Yosemite was a massive design change, we aren't expecting a major upheaval in the new version. What we may see are a few system-wide interface tweaks. For example, there are rumours that the new San Francisco font found on the Apple Watch will be making its way to OS X as well as iOS 9. Currently, the system font in iOS 8 and Mac OS X 10.10 Yosemite is Helvetica Neue. However, we've heard that the new font may not look great on non-Retina screens - after all this font has presumably been chosen because it is clear on a small inch wide screen, why should that same font be used on a 27in display?
We also think that changing the system font could be a massive job - Apple and developers would have to redesign their apps to use the new font and given that they only did that last year with the introduction of Helvetica Neue we think it would be a big ask.
If you are wondering what the San Francisco font looks like, apparently the typeface is similar to Open Sans or Arial.
Will OS X 10.11 be customisable? OS X 10.11 Customisation options
If the popularity of the new Dark Mode provided in Yosemite is anything to go by, Mac users would love to have more customisation options. In fact there have been calls for more Dark Mode choices, suggesting there is a real hunger for this kind of customisation.
Another suggestion is that certain interface elements could be tweaked, for example, those who don't like the fact that the green 'traffic light' in an application's menu now switches you to full screen could revert to the previous action of enlarging the window.
What stability and speed improvements will OS X 10.11 offer?
As we have already mentioned, the rumour is that OS X 10.11 will focus on stability rather than flash new features. This suggests that OS X 10.11 will have a lot in common with OS X 10.6 Snow Leopard, which bought bug fixes, optimization and security enhancements. Apple called it Snow Leopard because it was building on its predecessor Leopard.
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