$email = "example@email.com"; if(filter_var($email, FILTER_VALIDATE_EMAIL)) { echo "Valid email address"; } else { echo "Invalid email address"; }In this example, the filter_var function is used with the FILTER_VALIDATE_EMAIL constant to check if the $email variable holds a valid email address or not. If it is a valid email address, the script will echo "Valid email address", and if not, it will echo "Invalid email address". The function isEmail is commonly included in various PHP packages and libraries, including the Symfony Validator component and the Laravel Validation package.