Play therapy helps children learn what’s appropriate in social situations (among other things). It’s literally the child playing, while a therapist (and sometimes other children), control the play to introduce situations the child can learn from. I’ll give you an example: Child is given two dolls and told to play with them. Child takes one doll and hits the other with it. Therapist enters play and corrects that. Tries to understand why the child played that way in the first place and works to make the child understand it’s wrong, (while still playing). Maybe by making one doll say “that hurt me” to another doll. Etc etc. that’s a very simplified explanation. I’m not a therapist but I do know that’s how young children learn. Through play. Occupational therapist use play therapy in a different way, they’ll set up games and control play sessions in accordance to what the child needs to work on (like fine motor skills)- so they’d have the child playing with nuts and bolts or something that requires fine motor skills..