Session creation in PHP

In PHP, a session is created when you call the session_start() function. This function initializes a new session or resumes an existing one, and sets up the necessary data structures to store session data.

Here’s an example of how to create a new session in PHP:

<?php
// Start a new session
session_start();

// Set session variables
$_SESSION["username"] = "john";
$_SESSION["age"] = 30;

// Output session ID
echo "Session ID: " . session_id();
?>

In this example, the session_start() function is called to start a new session. The $_SESSION superglobal array is then used to set two session variables, “username” and “age”, to the values “john” and 30, respectively. Finally, the session_id() function is used to output the session ID.

Note that the session_start() function must be called before any output is sent to the browser, otherwise you will get an error. Additionally, the session_start() function must be called on every page that needs to access the session data.