Apr 26th, 2013 at 08:43 PM

Boolean: A boolean variable represent truth, supporting only two values: TRUE/true or FALSE/false. Alternatively, you can use 0 (zero) to represent FALSE, and any nonzero value to represent TRUE. example: $alive=false; echo $alive; // output false $alive=1; echo $alive; //output true $alive=-1; echo $alive; //output true $alive=5; echo $alive; //output true $alive=0; echo $alive; //output true