How does Deep Learning work?

Deep Learning is a machine learning method. It allows us to train an AI to predict outputs, given a set of inputs. Both supervised and unsupervised learning can be used to train the AI. We will learn how deep learning works by building an hypothetical airplane ticket price estimation service. We will train it using a supervised learning method. We want our airplane ticket price estimator to predict the price using the following inputs (we are excluding return tickets for simplicity)