title: How does PHP PDO's prepared statements prevent sql injection? What are other benefits of using PDO? Does using PDO reduce efficiency?
body: <p>I have been spotting the sentence <code>PHP PDO's prepared statements prevents SQL injection</code>. </p>
  
  <blockquote>
    <ul>
    <li>How does php PDO's(PDO's prepared statements) prevent sql injection?</li>
    <li>What are other pros/cons of using PDO(PDO's prepared statements)?</li>
    <li>Does using PDO(PDO's prepared statements) reduce efficiency?</li>
    </ul>
  </blockquote>
  
  <p>I have read this: <a href="https://stackoverflow.com/questions/134099/are-pdo-prepared-statements-sufficient-to-prevent-sql-injection">Are PDO prepared statements sufficient to prevent SQL injection?</a>
  But the data there is not completely clear.</p>