An okay listen. Steve presented his model to explain how we humans work, mostly from a childs perspective, but much was also applicable to us adults. In the model there is 'the human', that is our rational and conscious mind. Then there is 'the chimp', which is an automatic, emotional and insecure part that that is kind of egocentric and concerned with self preservation. The third part is 'the computer', which I'm not 100% exactly what it does, but I think it has something to do with automatic memory recollection, behaviours, and habits.
I found a lot of useful advice in this book on how to look at how we function, and how to both manage ourselves, as well as our loved ones. One such trick is to acknowledge when 'the chimp' takes over and we act with e.g anger or defensiveness in non-productive, and sometimes harmful manners. Steve calls this the 'chimp hijack'. Letting your rational 'human' manage your emotional and short sighted 'chimp' seems to be the solution to many of our behavioural problems. For instance, I don't like cleaning, or rather, my chimp doesn't like cleaning while my human likes it being clean. A trick is then to visualize how it would look like if it was clean, and then maybe that will convince the chimp to do it.
That being said, I'm not sure how much I really liked the model. First of all, I don't like the names as they are very misleading. Why call some part 'human' when all of them are equally human, and why call some part 'computer' when in the end that's what the whole brain really is. 'The chimp' maybe makes a little sense, even though real chimps probably also have a 'computer' in their brains themselves. It just feels too simplistic, and in the end, I don't really know what they correspond to in more established models found in the literature. I suppose it's to make it easier to explain to children, and some easy way to visualize and remember how we work in order to improve our behaviour. For that part, it does serve its purpose.