Bracketing is the process where a several images are collected with differing settings.
Most commonly, exposure is varied using exposure compensation
Other variables which can be bracketed are
- White balance
- Depth of Field / Aperture
- Flash Exposure
Bracketing can be used as a safety measure, so that a single best image can be later selected, or so that the set of images can be merged, as in HDR or Focus Stacking.