What does "who can see this group" mean?

[carlokok]

there’s a setting on the groups page; “Who can see this group”; if I set that to public; my group messages will still be hidden right?

[mikechristopher]

Yes the category security is something different.

All this means is that people can see the group exists on the group page here: Discourse Meta

They can also see who is a member of it etc.

[tophee (Christoph)]

It might be worth adding that the setting “Everyone” has a different meaning depending on whether the forum is public or private. In public forums “Everyone” basically means “the whole world”. In a private forum (i.e. which require users to login to see anything), it means “all logged in users”.

See also:

More nuanced group visibility (based on group membership)

Continuing the discussion from Hidden Group Membership: How about more than the current four visibility levels? Probably the most frequent use case for this would be to allow group members to apply for membership in sub-groups without having to make those sub-groups public. So let’s say you have a group for all members in an association, then those members (and only those) should be able to see various thematic working groups or what have you, either as a matter of transparency or in order to m…

[gordon_mrmoco (Gordon)]

У меня в группе с уровнем доверия 1 около 40 участников. Видимость группы установлена как «для всех», но они не видят друг друга. В чём причина?

[codinghorror (Jeff Atwood)]

Это автоматическая группа — у автоматических групп нет тех же правил или поведения, что и у ручных групп.