This chapter focuses on the definitions and basics of artificial intelligence (AI)Artificial intelligence (AI) and machine learning (ML)Machine learning (ML) in science in general and sports science in particular. After the classification and structuring of AI and ML in general science, the ML research landscape is then reflected on with a special focus on sports practice and sports science. It is shown that ML-based approaches already exist in numerous sports such as soccer, volleyball, field hockey, tennis, badminton and basketball, but have not yet found their way into sports practice to any significant extent. Although event and position dataEvent and position data are now generated as standard in many sports, they are used almost exclusively for basic research purposes. On the one hand, however, performance-relevant metrics for training and competition could already be developed on the basis of ML. On the other hand, ML can contribute to the development and testing of theories in various areas of sports science and sports informatics in the future.