Heredoc's are a great alternative to quoted strings because of increased readability and maintainability. You don't have to escape quotes and (good) IDEs or text editors will use the proper syntax highlighting.
A very common example: echoing out HTML from within PHP:
$html = <<
- $something
- $whatever
- $testing123
HTML;
// Sometime later
echo $html;
It is easy to read and easy to maintain.
The alternative is echoing quoted strings, which end up containing escaped quotes and IDEs aren't going to highlight the syntax for that language, which leads to poor readability and more difficulty in maintenance.
Of course you wouldn't want to see an SQL query highlighted as HTML. To use other languages, simply change the language in the syntax:
