This is a hardware or software set-up that functions as a translator between two dissimilar protocols. A gateway can also be the term to describe any mechanism providing access to another system (e.g AOL might be called a gateway to the Internet).
Combining Email Marketing with Other Types of Marketing
Whether you choose to do your marketing online or offline, one thing does not change. This is the concept that no single marketing strategy will be as effective as a combination of two or more marketing strategies.