Abstract : The integration of artificial intelligence (AI) into healthcare is not simply an evolution but an ongoing revolution that is fundamentally redefining medical practice. Medical AI is much more than a tool, it is a new frontier in contemporary medicine. As staple in hospitals and doctors’ offices worldwide, AI systems now assist healthcare providers by analyzing massive amounts of medical data and offering personalized diagnoses and treatment recommendations. In this first article, we will review some key definitions and concepts related to AI and then describe the different stages of AI development by placing them in a historical context. In a second article, we will focus more specifically on the various applications of AI in medicine, highlight some challenges and limitations, and open up some perspectives for the relatively near future.