Smart Objects are Photoshop layers that preserve original image or vector data, giving you the flexibility to experiment with different transformations and filtering. Smart Objects are particularly well suited to raw files. If edits in Photoshop would benefit from different raw processing, simply double-click the Smart Object layer to adjust the original data in the Camera Raw dialog box.
NAPP instructor Matt Kloskowski walks you through the process in this helpful video.
For more details about Smart Objects and other flexible, layer-based editing techniques, check out these topics in Photoshop Help: