how to use arrays?

Answer 1

if you are access the array data use array index
array index start must be 0
$arr=array("Ashvin","Kino","Many_More");
echo $arr[0];
echo $arr[1];

Answer 2

Example.
$test = array("Name1"=>"David","Name2"=>"Alex","Name3"=>"Martin");
echo $test[Name2]; // Otputs 'Alex'