6.2b Browser compatibility
The Web page must be compatible with the most recent and penultimate versions of common browsers. Browsers for all popular operating systems (such as Windows and Macintosh) should be considered.
The FAO's Internet logs show that the most common browsers are:
The term "browser compatibility" basically means that your Web site will appear and function the same on the screen irrespective of the type of browser software you are using.
The standards for browsers (to translate HTML pages) are established by the World Wide Web Consortium (W3C). The W3C is an international consortium where Member organizations, full-time staff and the public work together to develop Web standards. There has been considerable interpretation of W3C's rules by software companies. The result is that not all browsers display an HTML page in the same way.
For example, W3C HTML standards advise that the "table" tag should support a "cellspacing" attribute to define the space between parts of a table. However, standards do not define the default value for that attribute, so unless you explicitly define "cellspacing" when building your page, two browsers may show different amounts of white space in your table. In addition, browsers do not support Cascading Style Sheets (CSS) to the same level of accuracy, especially advanced CSS functions.
Often the main reason for why the same Web pages appear different is related to the HTML errors that are part of the page coding. In practice, the major browsers are robust and forgive many of these HTML errors. However, not all browsers forgive the same errors: your favourite browser may display your Web page without error, but a different type of browser may be seriously affected by the same error.
Hints to achieve browser compatibility