7. Presentation

Key Concepts

introduction
formats/compression
web browsers
network
scaling
monitors
image quality
guidelines

additional reading

WEB BROWSER CAPABILITIES
The Web supports few raster file formats: JPEG, GIF, and incomplete support for PNG. Other formats require use of a specialized viewer, such as a plug-in, applet, or some other external application. This limitation tends to dampen use as it places more demand on the user's end. In some circumstances, the value of the format is sufficiently compelling to overcome user resistance, as is the case with PDF files. Adobe lessens user constraints by supplying a browser plug-in with its PDF reader. If the stand-alone Acrobat Reader is already available when the browser is installed, most will self-configure to launch it when a PDF file is encountered. Some institutions convert non-supported formats or compression schemes on the fly to ones that are Web-supported (e.g., wavelet to JPEG) in response to user request.

NETWORK CONNECTIONS
Users probably care most about speed of delivery, as noted earlier. Several variables control access speed, including the file size, network connections and traffic, and the time to read the file from storage and to open it on the desktop.

© 2000-2003 Cornell University Library/Research Department