The Screen and Colors
* Case Sensitivity
although a server issue and not a browser one, most server software is case sensitive. Always create links using file names that match the case of the actual file that is being accessed. That way, even if the target server is not case sensitive, no maintenance will be required should the site be transferred to one that is.
* Color Issues
every monitor and color card displays colors differently. You can never assume that the shade of blue you are seeing will match the shade of blue that a visitor sees. In addition, not all browsers are capable of handling the text definition for a color. Use the HEX color definition codes instead of the corresponding words.
Avoid using the FONT color tag. Not only is this tag depreciated in current Web standards, but many users with color blindness, or those with other visual problems, set their own default colors which they will not appreciate being overwritten by your choices.
When specifying colors for any design element, put the tags into your CSS file rather than in the HTML directly.
Use only "Web Safe" colors that can be seen by anyone whose monitor and video card supports only the basic 256 color cube.
* Graphic Design Considerations
In order to assure compatibility across all graphic-enabled browsers, use only GIF, JPEG and PNG formats. . Keep in mind that some browsers are eliminating support for GIF files due to patent issues affecting the underlying LZW compression process.
PNG is an acceptable substitute for GIF. Other formats, including PICT, BMP and XBM are not widely supported yet.
* Fast Page Loading Considerations
Specifying the WIDTH and HEIGHT attribute for every graphic file allows the page to load faster because the browser can reserve space for the slower loading graphic files while it continues to render the textual portions of the page. Slice large images to speed up loading time.
* Screen Size Considerations
Never design a site with specific page height and width hard coded. Users with older monitors and video cards will not be able to easily view certain screen sizes, and other users have to stay within specific screen size settings due to default font size or other reasons. Screen sizes are also limited by people who use WEB-TV and similar services or who surf the web using handheld devices. Instead of defining absolute pixel sizes, use percentage settings whenever possible.