Review on Simple Machines by Joshua Paulson

I have used this since 2014 when it was called simpleforums. This is an excellent platform for forums that can be easily customized to meet your needs! It will take some time but once you get it setup correctly it's easy to administer! There are numerous plugins available from 3rd parties which you can use or integrate yourself if desired - including multiple themes (which gives more options then just plain default). We use it internally at our church where users create their own user groups with various permissions based upon roles they play within the organization.