Self Referential Associations in Rails - simpler than it sounds

Tbh I had no idea this was even a thing until recently. I've been working with Rails for a while now and somehow never came across it. So let me explain it the way I understood it. You know how we normally do associations in Rails, User has many Posts, Post belongs to User. Two different models, two different tables. Simple. But what if a model needs to reference itself? Like same table, same model, but pointing to another record in the same table? That's all a self referential association is. T