PSD - (Adobe Photoshop format) is the only format supporting all available image modes (Bitmap, Grayscale, Duotone, Indexed Color, RGB, CMYK, Lab, and Multichannel), guides, alpha channels, spot channels, and layers.
PNG - (Macromedia Fireworks format) create, edit, and animate Web graphics using a complete set of bitmap and vector tools. use export controls to optimize your images, give them advanced interactivity, and export them into other HTML editors. allowing you to launch and edit Fireworks graphics from inside Dreamweaver or Macromedia Flash.
Ai and EPS - formats, see what is 'vector shape graphics'.