Electronic commerce (e-commerce) refers to both financial and informational electronically mediated transactions between an organization and any third party it deals with. So e-commerce involves management not only of online sales transactions, but also of non-financial transactions such as inbound customer service enquiries and outbound email broadcasts, so you can argue that e-commerce is open to all online organizations.
However E-business or digital business is similar to e-commerce but broader in scope and refers to using digital technology to manage a range of business processes incorporating the sell side and buy-side e-commerce, and also other key supporting business processes including research & development, marketing, manufacturing and inbound and outbound logistics. (FYI)
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