NextDoor.com is a public neighborhood forum for you to post just about anything. It might be things happening around your neighborhood, any type of activities, car break ins, suspicious people walking around, etc.
Just by my experience most of the people who post their comments, complaints, etc, are women (about 95%). If you're a man and post or comment on something that the women don't like you will be attacked or bullied by women. Also, the forum is operated and monitored by women. I guess you can say that NextDoor.com is a place where women can fill empowered about themselves because they have no other place to go. Its a man's world and women don't like that!