# Using the calendar

In Castmill you need to use a calendar in order to decide when a given piece of content is going to be displayed. Calendars are very powerful with many options but in this guide we will use the simplest possible option which is setting a "default playlist".

In order for a player to reproduce any content it must have at least one Calendar attached to it. All new players are by default attached to one unique calendar. The easiest way go to this calendar is by going to the Players tab, select the desired player and then click on "View" for the Main calendar:

![](/files/-M_LS3Ax29tvH41S71TH)

By clicking on "View" it will open the Calendar attached to this Player:

![](/files/-M_LSnyGKn2AtpshH1q3)

As mentioned, the Calendar has many options, but the simplest we can use is to set a given Playlist as "Default". A default playlist will play when there is nothing else to play.

So lets click on the "Default" checkbox:

![](/files/-M_LTLmxCYtfCJbslblB)

Now if we check our Chrome player, it will be display the image.

![](/files/-M_LTsDOC9Exp8pwwpUG)

It has been a lot of steps to get us here. But hopefully you have also learnt how you can now create much more complex scenarios. In the rest of this documentation you can find a lot more information so that you can maximize what you can get out from Castmill. And if you need more help, please do not hesitate to [contact us!](mailto:support@castmill.com)


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