PNG is generally the best format to use

  • JPEG
    • JPG files are best for photographs or artwork with gradient tints because they support thousands of colours. JPG files are easily compressed but drop photo quality easily,
  • GIF
    • GIF images are best for line art or artwork with flat areas of colour such as text rendered as an image.
    • Gif images are compressed by removing colours from its palette of 256.
    • GIF images support transparency.
    • GIF is an older file format that is being superseded by PNGs.
  • PNG
    • PNGs provide all the advantages of GIFs with a greater colour range support
    • They compress much better than GIFs
    • PNG images support transparency