What are the limitations of using PHP to control user navigation on a webpage?

One limitation of using PHP to control user navigation on a webpage is that PHP is a server-side language, so it cannot dynamically change the page without reloading it. To overcome this limitation, you can use AJAX to make asynchronous requests to the server and update specific parts of the page without refreshing the entire page.

// Example of using AJAX to dynamically load content without refreshing the page

// HTML code
<button onclick="loadContent()">Load Content</button>
<div id="content"></div>

// JavaScript code
function loadContent() {
  var xhttp = new XMLHttpRequest();
  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
      document.getElementById("content").innerHTML = this.responseText;
    }
  };
  xhttp.open("GET", "content.php", true);
  xhttp.send();
}

// content.php
<?php
echo "This is the dynamically loaded content.";
?>