In what scenarios should meta tags or JavaScript be used instead of the header function for redirection in PHP scripts?

Meta tags or JavaScript should be used instead of the header function for redirection in PHP scripts when you need to perform the redirection after some content has already been sent to the browser. This is because the header function must be called before any output is sent to the browser. In such scenarios, using meta tags or JavaScript to redirect the user is a suitable alternative.

// Example of using JavaScript for redirection
echo "<script>window.location.href = 'https://www.example.com';</script>";