The last decade has seen a huge progress in a wide variety of applications related to the area of artificial intelligence, from speech recognition to computer vision, from natural language understanding to machine translation. Most of these improvements have been achieved by Deep Learning, a big trend in recent AI research, which goes back to multi-layered neural network architectures inspired by the human brain. Big companies such as Facebook, Google, Microsoft and Baidu are investing more and more resources in order to push forward with this novel technology. In this seminar, I will present some of the models and algorithms developed in the context of Deep Learning, together with some applications and a few criticisms which have recently been raised.