The latest version of macOS is macOS Ventura 13.5, which was released in July 2023. macOS Ventura is the eighteenth major release of the Mac operating system and was introduced at WWDC 2022. Apple releases a new major version roughly once every year, and these upgrades are free and available in the Mac App Store. To check which version of macOS is installed on your Mac, click the Apple menu icon at the top left corner of your screen, and then select the "About This Mac" command. The name and version number of your Macs operating system will appear on the "Overview" tab in the About This Mac window.