display:none Parent, display:block Descendant:

Source:

<div style="display:none">
    <p>Non-displayed paragraph</p>
    <span style="display:block">Is this span displayed?</span>
</div>

Result:

Non-displayed paragraph

Is this span displayed?

visibility:hidden Parent, visibility:visible Descendant:

Source:

<div style="visibility:hidden">
  <p>Non-displayed paragraph</p>
  <p style='visibility:visible'>This paragraph has style <code>visibility:visible</code>, and is within a DIV with style <code>visibility:hidden</code></p>
</div>

Result:

Non-displayed paragraph

This paragraph has style visibility:visible, and is within a DIV with style visibility:hidden


Offscreen parent:

Source:

<div style="position:absolute; left:-300px;">
    <p>Non-displayed paragraph</p>
</div>

Result:

Non-displayed paragraph