Question

can any one please let me know the basic differences between

$GLOBALS["test"] and global $test

and, will it make sense that, if i use $GLOBALS["test"] instead of $_SESSION['test']?

Answer 1

and, will it make sense that, if i use
$GLOBALS[“test”] instead of
$_SESSION[‘test’]?

No, session is different thing from a variable that is available globally.

$GLOBALS

An associative array containing
references to all variables which are
currently defined in the global scope
of the script. The variable names are
the keys of the array.

http://php.net/manual/en/reserved.variables.globals.php

Explanation:

$GLOBALS is an associative array available throughout your script, there is no need to use global $test

Note: This is a ‘superglobal’, or
automatic global, variable. This
simply means that it is available in
all scopes throughout a script. There
is no need to do global $variable; to
access it within functions or methods.