Depends on how you want to do it.
But which ever way, include() is not what you want to be using.
<?
$myVariable = file('/path/to/file.html');
?>
will result in an array containing each line of the file as an array element.
<?
$fp = fopen('/path/to/file.html','r');
$myVariable = fread($fp,filesize('/path/to/file.html'));
fclose($fp);
?>
will return a single string containing the contents of the entire file.
Which one to use?
That depends on your immidiate needs.
The first one is great for line by line parsing, such as CSV files, the second one is more general use for nadling a bulk string to be tossed where ever and trweated as a single unit.