WordPress Request Flow

1. Browser Sends the Request

• The user enters a URL in the browser (e.g., https://example.com/blog).
• The browser sends an HTTP request to the web server hosting the WordPress site.

2. Web Server Receives the Request

• The web server (e.g., Apache, Nginx) looks at the URL and processes it.
• For WordPress, front-end requests are directed to the index.php file in the root directory. For admin requests (e.g., accessing the dashboard), the server directs the request to the appropriate file in the wp-admin directory.

3. PHP Interpreter Executes Code

• Once the web server hands over the request, the PHP interpreter processes the PHP code.
• WordPress starts by loading index.php, which loads the core files required to set up the WordPress environment, plugins, and themes.

4. MySQL Database Interaction

• If the request involves dynamic content (such as posts, pages, or user data), WordPress communicates with its MySQL database.
• The WP_Query class runs queries to retrieve content like posts, pages, categories, custom fields, etc., from the database.

5. PHP Generates HTML, CSS, and JavaScript

• The PHP code dynamically generates HTML based on the requested page, pulling in the relevant CSS and JavaScript.
• WordPress also loads the active theme’s template files (such as header.php, single.php, footer.php) and runs any active plugins.

6. Web Server Sends Response

• The web server sends the final HTML document (along with the CSS, JavaScript, and other assets) back to the browser.

7. Browser Renders the Page

• The browser receives the HTML and renders it, displaying the content along with any CSS styling and JavaScript functionality for the user.