Circles allow people to create their own groups of people/colleagues/friends. Those groups of people (or circles) can then be used by any other app for sharing purpose through the Circles API
The Circles app is installed and enabled by default since Nextcloud 22.
You can use the \Psr\Container\ContainerInterface, see dependency injection, to get the \OCA\Circles\CireclesManager class, see our API documentation for its interface.
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