Apple today reminded Mac owners that they can download OS X 10.11, aka El Capitan, free of charge starting tomorrow.
If the Cupertino, Calif., company follows past practice, it will add El Capitan to the Mac App Store around 10 a.m. PT.
The upgrade will run on the same Macs that now run last year’s Yosemite, 2013’s Mavericks, 2012’s Mountain Lion and 2011’s Lion, according to Apple’s system requirements. That means more than nine of out 10 Macs which were online in August should be able to install El Capitan.
This year’s version of OS X will be the third that Apple has handed out for free, a zero-dollars pricing it introduced with Mavericks. That, in turn, should trigger an immediate surge in its user share, an estimate of the percentage of all Macs running the operating system. The last two editions, Yosemite and Mavericks, accumulated user shares of 37% and 32%, respectively, by the end of their first full month of availability.