PSD

PSD stands for "Photoshop Document". It is the standard storage format for Photoshop files. A PSD file stores an image with all available Photoshop options.

PSD files can contain layers, masks, transparency, alpha channels and much more. This is the main difference to other common formats such as JPG or GIF, whose main focus lies in portability and small memory requirements and not in the most comprehensive storage of editing options.

Due to the popularity of Photoshop, PSD files are also supported by most competing image editing programs. PSD files are also used by other Adobe products.

Advantages:

- Uses all the functionalities of Photoshop

- High image quality

Disadvantages:

- high memory requirements