Save a master version of an edited image in the PSD format to retain adjustment layers and other Photoshop features for future editing.

Save additional copies of a photo in formats that are best for specific uses:

• Save a photo as a JPEG for online use. The JPEG format flattens any layers into a single layer, so it’s a good idea to keep a layered PSD, too. Try not to re-save a JPEG often, because each time you make a change and re-save a JPEG the image loses some information.
• Save as a PNG for online use when you want to retain any transparent pixels, like a background that you deleted. The PNG format, like the JPEG format, flattens any layers into a single layer.
• Save as a TIFF for commercial printing if a TIFF file is requested by your print vendor. TIFF files, like PSD files, can retain layers.