Due to recent advances in machine learning there have been in the last few years a new interest in biometric identification powered by these techniques. Among them is Gait Recognition, which tries to use the characteristic way in which one walks as the identifying biometric element. Gait Recognition has the potential to be a major technology in person identification, as it can be performed at distance and without the need for the subject to be close to the camera. Two main ways to perform Gait Recognition have been developed: appearance based and model based. Appearance-based methods are currently more precise, but because it uses features directly inferred from videos, it can be subject to spurious correlations.