Create web content events
In addition to regular events that occur at a specific date and time, Google Calendar also supports special events on calendars that reference content on the web in a small pop-up window. We call these "web content events" because they let you pull in other content on the web that's related to a date, but not a specific event that you need to attend. Web content events appear as an icon at the top of each day and provide additional information when you hover over them or click on them, depending on how much information is available.
We've provided some examples of calendars with web content events that you can overlay on your main calendar under the 'Browse Calendars' tab (In the Calendars list on the left of the page, click Settings->Add Other Calendar->Browse Calendars). You can add the phases of the moon calendar so you can always see where you are in the lunar cycle, or a calendar of Google Doodles to always keep up to date on the special logos that appear on the Google home page. For more information on the web content events provided by Google Calendar, please visit What additional features and special events can I add to my calendar?
Web content events aren't just limited to these calendars however -- in fact, we're pretty excited about the possibilities. You could create a calendar that links to important news on your website, a calendar that shows trailers of movies as they are launched, or maybe financial news about your portfolio. The point is that now calendar publishing isn't just about events at a certain time and place but really anything related to a date that you might want to see on your calendar.
If you can publish information on the web (in other words, you can publish an iCal feed of events on your own site), we've given you the capability to create web content events yourself. Keep in mind that you have to be able to create and host an iCal file or use the Google Calendar Data API to publish calendars with web content. Please click a link below for tips on creating your own web content events: