Apr 27th, 2013 at 12:11 AM

Null: Null, a term meaning "nothing". Null does not mean blank space, nor does it mean zero; it means no value, nothing. In PHP , a value is considered to be null if: -> It has no been set to any predefined value. -> It has bee specifically assigned the value Null. -> It has been erased using the function unset(). The null datatype recognizes only one value, Null: <?php $default=Null; // here $default is a null variable. ?>