What exactly is this $_server do ?

Question

i'm new as hell in programming. its not getting in my server yuno..

Answer 1

$_Server is a superglobal array wich offers you informations about the server your script is running on.
Sometimes it is important, to check if the server does have all the requirements installed therefor you could use this variable.
for example if there is a special Version of PHP installed or a needed module.