People often refer to elements such as p, h1, or div as block-level elements. This means
they are elements that are visually displayed as blocks of content, or “block boxes.”
Conversely, elements such as strong and span are described as inline elements because
their content is displayed within lines as “inline boxes.”
It is possible to change the type of box generated by using the display property. This
means you can make an inline element such as an anchor behave like a block-level ele-
ment by setting its display property to block. It is also possible to cause an element to
generate no box at all by setting its display property to none. The box, and thus all of its
content, is no longer displayed and takes up no space in the document.
There are three basic positioning schemes in CSS: normal flow, floats, and absolute posi-
tioning. Unless specified, all boxes start life being positioned in the normal flow. As the
name suggests, the position of an element’s box in the normal flow will be dictated by that
element’s position in the (X)HTML.
