What are the implications for user experience and SEO when hiding the true URL in the address bar using PHP?

Hiding the true URL in the address bar using PHP can potentially confuse users and make it difficult for them to understand the structure of the website. This can lead to a poor user experience as users may not know where they are within the site or how to navigate back to certain pages. Additionally, from an SEO perspective, hiding the true URL can impact search engine rankings as search engines rely on URLs to index and rank websites.

// Redirect to the true URL if a hidden URL parameter is set
if(isset($_GET['true_url'])){
    $true_url = $_GET['true_url'];
    header("Location: $true_url");
    exit();
}