The model is a model proposed by Daniel Dennett is in the (1991) book 'consciousness explained.'
I am more than a little nervous of attempting to summarise the book, but the broad thrust, at least as I understood it, is that the brain generates different 'explanations' of events, which are affected by subsequent events… and that the brain then continuously re-interprets these 'explanations' in a way that may affect what we believe we believed!
In terms of what we believe at any given time, the multiple drafts model postulates, for want of a better explanation, the idea that the brain is not a 'top-down' device, but instead more akin to a plethora of different subsystems, with may each have different interpretations… and that the prevailing belief is the 'majority opinion' of such subsystems.
By Dennett's own admission, the model is incomplete, but represented, ~1990 his understanding of conciousness in the light of evidence available at the time.
I'm sorry, but I can't get this down to Quora-sized answer, and strongly recommend a read of the book if you are interested.