OS X
The macOS version was known as iCal before the release of OS X Mountain Lion in July 2012. Originally released as a free download for Mac OS X v10.2 on September 10, 2002, it was bundled with the operating system as iCal 1.5 with the release of Mac OS X v10.3. iCal was the first calendar application for Mac OS X to offer support for multiple calendars and the ability to intermittently publish/subscribe to calendars on WebDAV servers. Version 2 of iCal was released as part of Mac OS X v10.4, Version 3 as part of Mac OS X v10.5, Version 4 as part of Mac OS X v10.6, Version 5 as part of Mac OS X v10.7, Version 6 as part of OS X v10.8, Version 7 as part of OS X v10.9, Version 8 as part of OS X v10.10 and OS X v10.11, and version 9 as part of macOS v10.12.