Template Tags?

[php4ever]

What exactly are these three template tags for? And, how important is the placement of these in the template header and footer?

$spacer_open
$_phpinclude_output
$spacer_close

[calorie]

Both $spacer_open and $spacer_close are used to space contents within a page:

$spacer_open contains the content of the spacer_open template by default
$spacer_close contains the content of the spacer_close template by default
$_phpinclude_output may be used by mods but contains nothing by default

[php4ever]

Thank you calorie