As instruments for accurately measuring magnetic fields, atomic magnetometers play a significant role in various fields, including fundamental physics, earth sciences, biomedicine, and national defense. This study presents a comprehensive review of the technical development of atomic magnetometers, covering their major categories and basic features, while providing a detailed discussion of the current research status and development trends of alkali metal optical pumping magnetometers, coherent population trapping atomic magnetometers, spin exchange relaxation-free atomic magnetometers, and nonlinear magneto-optical rotation atomic magnetometers. The study first classifies magnetometers based on classical physics principles and quantum effects. This is followed by an in-depth discussion of the working principles, sensitivity, dynamic range, bandwidth, and other key performance indicators of the four types of quantum-effect atomic magnetometers. The study then describes their advantages and challenges under various application scenarios. Finally, future developmental directions for magnetometer technologies are considered. These include miniaturization, integration, enhancement of vector magnetic field measurement capabilities, and potential applications in biomedical imaging and geophysical exploration.