For positioned elements, defines how the element treats content whose rendered dimensions exceed the height and/or width of the container. Except for some types of content that demand a fixed width (a PRE element, for instance), the default behavior of an element is to respect the width attribute setting and handle the issue of overflow in the height of the element.

A setting of visible causes the containing block to expand to allow the full width (if fixed) and height of the content to be displayed. If borders, margins, and padding are set for the element, they are preserved around the expanded content block.

A setting of hidden forces the block to observe the height and width settings, potentially causing the content to be clipped by the size of the block. Borders and padding are preserved, but margins may be lost along the edges that clip the content.

A setting of scroll should generate a set of horizontal and vertical scrollbars inside the rectangle of the content block. The bars become active only if the content actually requires scrolling in any direction. In practice, scrollbars are displayed for this setting in Internet Explorer 4 for Windows, but not on the Macintosh.

A setting of auto should generate scrollbars only if the content in the block requires it. Again, this works correctly in IE 4 Windows, but not in IE 4 Macintosh.

Note that Navigator 4 does not provide direct control over the overflow attribute. It is in a perennial state that sizes the height of a block element to the height of the content of the element. Therefore, it is not practical to create empty blocks (with borders, for instance) in Navigator 4, unless you artificially fill the block with padding (which then negatively affects the display in Internet Explorer).