This lets you switch the operation of the payment system as
follows:
ON – the
payment system is active and is available for customers to select
for payment
OFF – the payment
system is disabled
TEST – the
payment system is set in test mode; it will only be visible at
checkout if you are logged in as a store admin. Orders will be
passed with a 'test' flag so cards will not be
billed.
FAKE – an additional
test setting; this simulates an order callback without sending
anything to the payment gateway. It is a useful way to test the
settings and see what happens with successful orders but without
having to repeatedly go through the payment stage on the remote
site.