E-commerce is the marketing, ordering and sale of goods and services over the internet. E-commerce transactions may be business to customer or business to business. The range of goods and services that can be bought or sold by e-commerce would appear to be without limit. The potential size of the market is enormous. It has been estimated that potential revenues from e-commerce are over US$1 Trillion.

E-commerce offers sellers of goods and services significant benefits when compared with conventional selling methods, the most significant of which are cost saving, greater flexibility and access to a truly global market place. For e-commerce businesses offering digitised products and services (such as computer software which the purchaser can download through the internet) virtually no physical presence is necessary. Even for e-commerce businesses which are offering tangible goods (such as books, electrical goods etc) the "physical portion" of the business e.g. warehousing and delivery, can be readily outsourced.