A comes before B.
A has lower value than B. Like 1 is lower than 2.
[man]strcmp/man
$x = strcmp( 'aaa', 'bbb' );
Compares 2 strings.
Returns <0 if string1 is lower than string2.
Or 0 if they are equal.
And >0 if str1 is bigger than str2.
Yes you can use variables in $message.
By putting doublequotes (" ") around the string.
Single quotes (' ') will not work.
I also think in this case would be good use newlines \n in message.
But I am not sure.
$message = "Congratulations for registering. Welcome to the private wow server.\n
The following is the information you used to register with.\n
Username: $name\n
Password: $pass\n
Email Address: $email\n
Expansion: $client\n";