INCLUDE | INCLUDE_ONCE | REQUIRE | REQUIRE_ONCE | HEADER
pre defined function
--------------------
the function which is already defined in the library of php
is called pre defined or inbuilt function.
for example strlen(), floor(), ord(), chr() , rand() etc.
include();
include_once();
require();
require_once();
header();
include(); and include_once();
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--include() function include file from another file it
may be html , php or any other type of file in the
whole page.
-- in include function if included file is not available then program will execute
without the included file without any fatal error.
#include
#include_once
#header
#require
#require_once