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I am fairly new to website design. I am currently coding a new site. I have a local server setup (localhost) using Apache and testing using Firefox Ver 21 and IE Ver 9. I am getting display differences between Firefox and IE. I am confused about IE compatibility mode. For my testing should IE compatibility mode in IE be set on (checked I suppose) or off (unchecked)? Any other suggestions on how to ensure the displays will be correct on different versions of IE? If I get the display like I want it in Firefox, some aspect is different in IE with compatibility off. If I turn compatibility on it might fix one issue but screw up another. I guess I just don't understand the correct process to attack the compatibility issues between browsers, if that makes any sense. Doing all the layout in CSS.