title: What is the difference between isMail and isSMTP
body: <p>I'm using PHPMailer and having a hard time getting isSMTP on bluehost to work.  I have been able to get isMail to work and am wondering what the difference is in sending mail.  Also, it seems that I'm getting a HELO or authentication error when trying to use isSMTP but bluehost says my setting are correct.  I'm using SSL and port 465.</p>