Helpers
RenderToPlaceholder
The RenderToPlaceholder helper allows you to render a template to an arbitrary string placeholder for output "somewhere else".
$this->renderToPlaceholder('some-template.phtml', 'myPlaceholder');
// Possibly in another template, perhaps a layout
echo $this->placeholder('myPlaceholder');
Bear in mind that if you wish to render a template within the current template, the partial helper is better choice.