PHP has a built-in `mail()`, but many production servers block it or mark emails as spam.
  
  Professional apps use SMTP via libraries like:
  - PHPMailer
  - Symfony Mailer
  
  ## Why SMTP is better
  
  - authenticated sending
  - better deliverability
  - attachments + HTML emails
  - clearer error handling
  
  ## High-level PHPMailer idea (example)
  
  ```php
  // composer require phpmailer/phpmailer
  // Then use SMTP host, username, password, and send.
  ```
  
  ## Best practice
  Never store SMTP passwords in code. Use environment variables.
  
  > Next: Background jobs, queues, and why you should not send emails inside web requests for heavy apps.

Send emails reliably using SMTP libraries, and understand why built-in mail() fails in production.

Sending Emails in PHP (SMTP, Safer Than mail())

Learn PHP programming for server-side web development. Master PHP syntax, functions, and building dynamic websites.

Sending Emails in PHP (SMTP, Safer Than mail())

Why SMTP is better

High-level PHPMailer idea (example)

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