Learning about float

Learning about float

In this article
http://coding.smashingmagazine.com/2007/05/01/css-float-theory-things-you-should-know/
it says. A floated box is positioned within the normal flow, then taken
out of the flow and shifted to the left or right as far as possible.
Content may flow along the side of a float. When a box is taken out of
normal flow, all content that is still within normal flow will ignore it
completely and not make space for it.
Can you give a simple example concerning floats where we have all content
that is still within normal flow will ignore it completely and not make
space for it.
//Tony