Compatibility
Because Google Calendar is a web-based application, it runs on virtually any operating system, provided that the OS has a browser which supports the required web technologies. Since it uses recent browser features, browser compatibility includes Microsoft Internet Explorer 6, 7, and 8; Mozilla Firefox 2.0+; Opera 9.5; Google Chrome; and Safari 2.0.3.
Google Calendar supports exporting calendar data through a permanent HTTP URL containing iCalendar data, either at a public or "private" (hard to guess) address. This bears resemblance to the Webcal "protocol". Public calendars were searchable until February 2009. The data can be integrated with, among many others, Novell Evolution, and Windows Calendar in Windows Vista (using the subscribe feature). The web link for the location of the calendar can be found in Google Calendar Settings in the Private Address section.
Google Calendar also supports CalDAV using iCal 3.x.
Read more about this topic: Google Calendar