Raster Images

Pixel-based graphics
Resolution-dependent: Images become pixelated when enlarged.
Good for: Photos, digital artwork and web graphics.

Vector Images

Curve-based graphics
Resolution independent: Image size can increase without losing resolution.
Good for: Logos, icons and type.

Image Color Formats

CMYK is optimized for physical printing. It is a 4-color printing process that stands for Cyan, Magenta, Yellow and Key (black).

RGB is optimized for screen viewing. it is a light-based color model that stands for Red, Green and Blue.