Does a standalone php file (e.g file1.php) require <?php ?> Tags?

Question

This is about when creating separate php files. Not directly into the page. Do they require <?php ?> Tags.

Answer 1

I didn't get what you mean by standalone PHP file. As I understand it, PHP processor distinct PHP code from other code possibly in same page by looking for the PHP code marker tags.

So I think it is necessary despite of whether the code was embedded in HTML, or written as mere PHP code.