I'm sure the terms mean even more things in other fields. It would be nice for Satheerthan to repost and give us the context in which he or she saw the terms used. That would let us narrow down the meaning pretty quickly. I believe primary and secondary marketing mean different specific things to the rest of the business world. Direct mail intended to gain check with order could be considered by some a form of primary marketing.
Cars are a good example of a product sold through secondary marketing.
Car companies advertise to get you to prefer their cars. Car dealers even advertise to get you to prefer their dealership. I suppose many companies do some of both. Organizations like FannieMae and FreddieMac that buy those loans to make more mortgage money available are the secondary market. That would let us narrow down the meaning pretty quickly.