Today we explore the concept of AI tutors as personalized learning tools, explaining their varying levels of autonomy from simple assistants to virtual teachers. We outline the technologies that enable AI tutors, such as Natural Language Processing and Reinforcement Learning, and details the benefits of their application, including personalized pacing, instant feedback, and increased accessibility. We also addresses crucial ethical concerns, particularly regarding algorithmic bias, behavioral nudging, and data privacy, before discussing current limitations and challenges like the digital divide and the potential for over-reliance. Finally, we projects future trends in AI tutoring, emphasizing integration with human teaching and the need for thoughtful governance and oversight to ensure equitable and effective implementation.