You'd rather add img {border:0;} to your CSS file and be done with it. It is faster and more efficient than adding border="0" to every image. If you do want to have a border for an image, simply specify it like you'd normally do (or better yet, with CSS). If you have the image inside a link (the a tag), you may want to remove the text-decoration as well.
The "invisible" dotted line is to represent the block the element occupies and is something that a browser adds. To avoid the borders I use "border-style: none;"
The border (outline, actually) that appears on clicking, and remains afterward is there to show focus. The default Firefox setting is :focus { outline: 1px dotted invert; } Code (markup): You are free to modify this behavior, but it is not recommended to mess with expected behavior. Read about this in the user interface section of the css specifications. cheers, gary