[[[From
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Activities that don't require a Google Account:
* Reading posts in public groups
* Searching for groups, posts, or authors
* Posting to groups via email if they are unrestricted or you're
already a member
* Joining a public Google Group via email
Activities that require a Google Account:
* Creating and managing your own Google Group
* Posting to groups via our web interface
* Creating pages and uploading files
* Subscribing to a Usenet newsgroup and receiving posts via email
* Joining a Google Group via our web interface
* Changing your subscription type (No Email, Abridged Email...)
* Reading a restricted group's posts online