<pre> with default tab-size of 8 space characters

without tab
	with 1 tab
		with 2 tabs

<p> with tab-size customized to 4 space characters and 'white-space: pre-wrap'

without tab with 1 tab with 2 tabs

<p> with tab-size customized to 4 space characters, but without 'white-space: prewrap'

without tab with 1 tab with 2 tabs

<pre> with tab-size set to 12 space characters

without tab
	with 1 tab
		with 2 tabs