Fast Hybrid AF is an auto focus system that combines the traditional Contrast detection AF with Phase detection AF. Combining both of these auto focus features is great for added precision and ideal for a quick response when tracking fast-moving subjects.
Even in Speed Priority Continuous Shooting mode, using auto focus tracking in each frame is possible because of the Fast Hybrid AF feature.
IMPORTANT: Fast Hybrid AF is available only with compatible lenses. If a lens does not have the Fast Hybrid AF feature, it will use the Contrast-detection AF by default.