print <<<END
This uses the "here document" syntax to output
multiple lines with $variable interpolation. Note
that the here document terminator must appear on a
line with just a semicolon no extra whitespace!
END;
Basically, it's for use with lots of code that only has small items of php in it. It's an easier way to write straight HTML in PHP as the PHP parser will only look for variables and replace the variable with its value.
Just remember, when using it:
You can use whatever you want to define it:
<<<END
<<<DOCUMENT
<<<HEAD
<<<SOMETHING
When ending it, it must come on its own line with NO WHITE-SPACE and terminate the line:
END;
DOCUMENT;
HEAD;
SOMETHING;
Read up with the user notes
~Brett