HF surface wave radar (HFSWR) has been recognized and accepted as an important tool for ocean remote sensing for more than four decades. In this article, a comprehensive tutorial of such an ocean sensor is presented. It begins with the concept of HFSWR. Next, the history of HFSWR is briefly reviewed. Then, the classification of HFSWR in terms of waveform, array signal processing technique, the number of operating frequencies, and configuration geometry is described in detail. Subsequently, the state‐of‐the‐art applications of this type of ocean radar for sea surface current, and wave parameter measurements, wind mapping, and hard targets detection and tracking are presented. The working principles and data processing associated with each application are also explained. The remaining challenges and future trends are also discussed.