css float and clear property

1. Explaintion:
The float proper can set the div or other as the layout that out of the regular, which is such a hidden man in the content, and others is not see this float block,
and the other content will layout there self deployment which ignore the float block and behaviour, ex wrap the div, which such there is no float block exist.

The clear proper is set to the other content block, that will know there has a float block, and it will new a layout to deploy itself



Reference:
w3c 
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