Your Google calendar can also be made publicly accessible, which allows coworkers to view schedules and posted events even if they are not included in the shared calendar. This is especially important when working in large groups, arranging workshops or setting up public events. You can make the address of calendar public, publish the calendar or embed the calendar on a web page.
Click the triangle icon next to the calendar's title and click Share this calendar. By choosing this option, the public will be able to view your calendar and it will be included under Google Calendar and Google search listings.
You also have the option to make the calender accessible to only people you have chosen. The calendar will be issued an address where selected users can view an HTML read-only version of the calendar. The address can also be used to make the calender accessible through various feed applications including Google Reader and Apple's iCalendar.

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After making the calendar public, the app will also generate a HTML code which can be used to embed the calendar into a web page. The code can be found by clicking the HTML icon next to the calendar's address in the settings section. You can also create a button to add to the web page that allows visitors to add your events to their calendars.

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Create the button by going to the calendar's settings page and clicking the XML icon to retrieve the calendar's address. Copy the address and go to Google's event button generator. Pick the event's date and fill out a brief description. Choose the button style and paste in the calendar's address. The generator will create the code for the event reminder button, which can easily be added to the web page.