An open standard file format originally introduced in 1998, iCal stores calendar information in a format that's easily shared between applications, both calendar and apps such as Microsoft Excel. The ...

It’s common to use a third-party calendar such as Google Calendar even if you also use Microsoft Outlook’s Calendar feature. One might use Outlook on your PC and Google Calendar on mobile devices.

If you’re a Google Calendar user, you may have had issues adding events to your calendar when someone sends them to you attached to an email in iCal format (the files usually looks like “invite.ics”).

Multiple calendars let you share calendars, but they can also complicate scheduling. Here's how to export and import Google Calendar data to reduce your number of calendars. Image: Andy Wolber / ...