title: How to generate a secure activation string in php?
body: <p>After user subscribe email to my website. My website will generate an email confirmation and send to them. In the email content, i need to include activation key, something like:</p>
  
  <p>www.domain.com/activate.php?key=$generatedKey</p>
  
  <p>How do you generate the key? using sha1($email)??</p>
  
  <p>After generate the key, i store it in database, so that when user click the link I can verified it with the database?? I am new to it, please advise.. I need an Email Confirmation script..</p>