// filter_var() function used to filters a variable
//with the help of a specified filter .
// in php language we use filter_var() To validate data such as email , ipAdress .etc.
// syntax is filte_var($varName , FILTER_VALIDATE_EMAIL );
//example
$email ="test@gmail.com";
if(filter_var($email, FILTER_VALIDATE_EMAIL){
echo" email adresse is valid ";
else{
echo " the email adresse is not valid " ; }