List of PHP control structures 
STATEMENT DESCRIPTION
the declare construct The DECLARE construct is used to set the execution directives of script codes.
the return statement The RETURN statement is used to return the flow control to the calling mode.
the require statement The REQUIRE statement is used to add the required file's source code into the source code where it is called from. If the file doesn't exist, the script is halted.
the require_once statement The REQUIRE_ONCE statement is used to add the required file's source code into the source code where it is called from if the file hasn't been added already. If the file doesn't exist, the script is halted.
the include statement The INCLUDE statement is used to add the required file's source code into the source code where it is called from. If the file doesn't exist, the script is NOT halted.
the include_once statement The INCLUDE_ONCE statement is used to add the required file's source code into the source code where it is called from if the file hasn't been added already. If the file doesn't exist, the script is NOT halted.
the goto statement The GOTO statement is used to lead the parser to jump to a different section of a program.