How does Django’s nested Meta class work?

You are asking a question about two different things:

1. Meta inner class in Django models:

   This is just a class container with some options (metadata) attached to the model. It defines such things as available permissions, associated database table name, whether the model is abstract or not, singular and plural versions of the name etc.

   Short explanation is here: Django docs: Models: Meta options

   List of available meta options is here: Django docs: Model Meta options

   For latest version of Django: Django docs: Model Meta options

2. Metaclass in Python:

   The best description is here: What are metaclasses in Python?