By what principle are model values ​​bound to form fields?

Question

Laravel

It became interesting ..
The model has a type_id
attribute. In the view, I bind the model to the form

{{ html()->modelForm($document, 'PATCH', route('admin.docflow.document.update.main', $document->id))->class('form-horizontal')->open() }}

and the text field itself is simply called type :

{{ html()->text('type')
 ->class('form-control')
 ->attribute('maxlength', 256)
 ->required() }}

the binding happened - the value from the model was put down in the form field. I looked at the source code, I can not quickly find something. Maybe someone knows the principle?