What is the negation of the AND operator when using if and else?

i'm using if with && and the else comes after that.

Example :

$Name == "john";
$age == "30";

if i do this :

if($Name =="john" && $age=="30") { some stuff } else { do other stuff }

Is the else here means : $Name !="john" && $age != "30" ?? i'm a little confused about that.

Thank you