DescriptionAllow to sweep through the focus range of auto focus lenses, and take a series of photos at different focus points. These photos can be combined in post processing (off camera), a technique called "focus stacking".
ExplanationFocus bracketed shots can be combined to guarantee higher sharpness throughout the frame. This is a great technique for macro as well as landscape photography. Google searches for "focus stacking" or "focus bracketing" show a number of tutorials and results. While this can also be done manually, manual focus changes will potentially change the camera position, making the post-processing more difficult because of alignment issues. In addition, for both macro and landscape photography it's desirable to have those shots in very short succession, to avoid moving of elements (flowers, insects, clouds etc.) between the frames.
Here's a tutorial on the Fujifilm Australia Youtube channel:Tutorial. It does not cover the part where they recorded it manually.