This book is an excursion inside the codes and schemes that mind uses in order to think. We know the efforts of making good guessing and the strain in solving complex problems. We also have experienced how difficult it could be thinking clearly when we are tired, anxious, hungry, or sleeping. Any second, in our life, our brain is literally flooded by a bulk of inputs, information, chemicals from lungs or blood, nutrients and vitamins from gut, or carbodioxide in a crowded environment. This book can be a pleasurable tool for understanding how we usually think and behave, but also what are the mental processes that generate biased thoughts, behavioural problems, or a difficult problem solving. Several theoretical models are used, and extensive explanations are given to make difficult concept approachable.