During the last ten years, power analysis attacks have been widely developed under many forms. They analyze the relation between the power consumption or electromagnetic radiation of a cryptographic device and the handled data during cryptographic operations. The goal of this paper is to give a global view of statistical attacks based on side channel analysis. These techniques are classified into two classes: attacks without reference device (e.g. Differential Power Analysis, Correlation Power Analysis) and attacks using a reference device (e.g. Template Attack, Stochastic Model Attack). In this paper, we present the attacks with an easy comprehensible way and focus on their implementation aspect. The pros and cons of each attack is highlighted in details with concrete electromagnetic signals. At least, our paper proposes also some solutions to enhance the existing attacks.