About Web Images

This assignment continues our study of graphics with a reading from chapter 11 of the Web Style Guide.


After completing this assignment, students should be able to

  • Identify and discuss the characteristics of the five file formats important for online images and listed in the table below.
  • Summarize the “best practices” for archiving web site images 332-33.
  • Explain the reasoning behind this recommendation: “Save your original uncompressed images!” (332).
  • Summarize the rules of thumb that apply when choosing the right file format for  images
Format Compression Ownership Best for
JPG Lossy Open Source Photographic
PNG Lossless Open Source Diagrammatic
GIF Lossless Now open source Diagrammatic
PSD (Adobe Photoshop) Lossless Proprietary Photographic
AI (Adobe Illustrator) Lossless Proprietary Diagrammatic


  • Lynch and Horton, 327-336
    (through “Photographs and Illustrations” on 336)