Guidelines for SLIM Web Pages

Principle 1: Minimize bandwidth impact.

• Keep pages to 25,000 bytes or less regardless of the audience. If pages exceed 25k, you will need to create a distinct link to a low bandwidth version.
• Keep home page topics to one 500,000 bytes or less.
• Ask the user if they want the assault of large (15k or more) image files. Don't just assume that they do, regardless of their speed. For example, this is what a link to an 87kb page would look like: A Fantastic page (87kb)
• Keep the number of colors in an image to 256 or less.
• Augment all images and clickable images with text alternatives. Remember, there are still a lot of people running with images turned off -even when they have T-1 access.
• If you must go for the photorealistic page, please use .JPGs instead of GIFs. JPG produce a much better image and file size tends to be smaller.

Principle 2: Test all graphics early and often on something other than the computer you are working on.

• Test on both graphic and text browsers.
• Your page may have great images that turn to ugly glop when applied to a different computers.

Principle 3: Make sure that the images add value.

• A string of buttons in an imagemap doesn't always add value. Images that show the relationship between the different items does.

Principle 4: Keep all navigation pages (the home page) to one screen.

• Keep the laptop user in mind - their screens have a 10.3 inch diagonal at most.
• The length of individual pages should be no more than 4 screens long. An exception is when it is more convenient for an individual to save a single file rather than multiple files such as an article or instruction. Even in these cases, a lengthy document should be broken into separate files giving viewers the option of opening the entire document or specific parts of the document.
• Include Back and Home navigation buttons - not all browsers have these buttons.
• Consider indexing your home page topics.

Principle 5: Every Page contains:

• distinctive file names so viewers can easily download pages.
• the name and electronic mail address of the data maintainer(s)
• the <address> tag at the bottom of every page. This identifies when the page was last updated.
• a navigational link or button that returns the viewer to the SLIM home page
• any known omissions or problems with the data
• a description, copyright notice, origin, and authority of the data (If appropriate)
• the frequency with which data is updated or expiration date (If appropriate)

Remember that good web page design considers 3 areas:

• Conceptual Design: matching appropriate content formats with the different types of information needs of target audiences
• Navigation Design: defining relations between pages
• Page Design: giving a page "look and feel" and navigation buttons or hyperlinks.