What are common mistakes when integrating PHP and jQuery code together?

One common mistake when integrating PHP and jQuery code is not properly passing PHP variables to JavaScript. To solve this issue, you can echo the PHP variables within script tags in your PHP file so that they are accessible to jQuery.

<?php
$php_variable = "Hello World!";
?>

<script>
var js_variable = "<?php echo $php_variable; ?>";
console.log(js_variable);
</script>