Windows Calendar is a calendar application that is included in Windows Vista. It natively supports the iCalendar file format, and has the ability to publish and subscribe to web-based calendars by using HTTP and WebDAV. Calendars may also be published to network drive shares.
Windows Calendar has several calendar views, including Day, Week (5 and 7 day) and Month, and also supports Tasks. Windows Calendar supports over 100 calendars for each user.
Windows Calendar has received criticism for bearing some resemblance to iCal.[1] Another issue is that Windows Mobile Device Center synchronizes with the Outlook calendar instead of Windows Calendar.[2]
Windows Calendar can be extended using the APIs included with the CF4 Developer kit.