Yale C/AIM Web Style Guide


Web Graphics


Color display primer

Graphic file formats

Interlaced GIF

Transparent GIF

JPEG graphics

Summary-File formats


Optimizing graphics I

Optimizing graphics II

Height & width tags

Colored backgrounds


Uses for GIF and JPEG files
Now that Netscape and other browsers are supporting both GIF and JPEG graphics in inlined Web page images you could use either graphic format for the visual elements of your Web pages. However, in practice most Web developers will continue to favor the GIF format for most page design elements, and choose the JPEG format mostly for photographs, complex "photographic" illustrations, medical images, and other types of images where the compression artifacts of the JPEG process do not severely degrade image quality.

Advantages of GIF Files

Examples of various GIF images.

The most widely supported graphics format on the Web

All graphic Web viewers support the GIF format for inlined images.
GIFs of diagrammatic images look better than JPEGs.
GIF supports transparency and interlacing.

Advantages of JPEG Images

Examples of JPEG images.

Huge compression ratios are possible, for faster download speeds.
Gives excellent results in most photographs and medical images.
Supports full-color images (24-bit "true color" images).
Copyright 1997 P. Lynch and S. Horton,
   all rights reserved. Yale University   Revised January 1997.