El Capitan is the final version to be released under the name OS X. Its successor, Sierra, was announced as macOS Sierra. El Capitan received much better reviews when compared to Yosemite.
The first beta of OS X El Capitan was released to developers shortly following the WWDC keynote on June 8, 2015.[2] The first public beta was made available on July 9, 2015.[3] There were multiple betas released after the keynote. OS X El Capitan was released to end users on September 30, 2015, as a free upgrade through the Mac App Store.[4]