Question: what are os x versions?
Answer: MacOS 10.14: Mojave- 2018., MacOS 10.13: High Sierra- 2017., MacOS 10.12: Sierra- 2016., OS X 10.11: El Capitan- 2015., OS X 10.10: Yosemite-2014., OS X 10.9 Mavericks-2013., OS X 10.8 Mountain Lion- 2012., OS X 10.7 Lion- 2011.