What B2G (Business-to-Government) is

An acronym that describes business-to-government relationships. With the government being the largest employer in the U.S., B2G is expected to become big business.

The meaning of E-business

Any business that is deriving revenue at least in part from something "electronic," usually on the Internet. It also refers to a strategy or service that enables a business to do more business because of Internet-related technology (see: Cisco, for example). The tendency for companies to put an "e" in front of a new product or service primarily comes from marketing departments that are trying to convince consumers they have an online strategy. The traditional brick-and-mortar firms that are starting an online component will use this marketing term to announce they are now online.