Inside a program or a custom function, control may be conditionally transferred to a statement identified by a line number or explicit label; if the target is 0 (zero) this terminates the program or returns to a function's caller.
Control may be conditionally transferred to a statement. This was inside a program. This was inside a custom function. This statement is identified by a line number. This statement is identified by explicit label. This terminates the program or returns to a function's caller. The target is 0 (zero).