CGSize to pixels / points confusion

Question

I have got this code:

CGRect _frame = container.frame;
CGFloat height = _frame.size.height

This code gives me the height of the view but in what units? Is there a way to convert it to pixels or points so I could visualize it a bit better?

I have read in the documentation that CGSize is a vector rather than a physical value but that doesn't me help much in understanding it.

Thank you!

CGSize documentation