What is the purpose of using sessions in PHP and how can they be effectively utilized to pass data between pages?

Using sessions in PHP allows you to store user data across multiple pages during a user's visit to a website. This is useful for maintaining user login status, storing shopping cart items, or any other data that needs to persist across pages. Sessions can be effectively utilized by starting a session at the beginning of each page where data needs to be passed, storing data in the session superglobal, and accessing that data on subsequent pages.

// Start the session
session_start();

// Store data in the session
$_SESSION['username'] = 'JohnDoe';

// Access the data on another page
session_start();
echo $_SESSION['username'];