Google/Groups

Google Groups
Google Groups - https://groups.google.com

Create and Browse
Create / Browse Google Groups - https://groups.google.com

Calendar
Use Google Calendar with Google Groups - Groups Help - https://support.google.com/groups/answer/60652?hl=en

Embed
Insert a forum into a webpage - Groups Help - https://support.google.com/groups/answer/1191206?hl=en