Encyclopaedia of e-Commerce is devised to provide teachers, students and laymen interested in e-commerce with clear concise, and correct definitions and descriptions of the ecommerce terms. The explanations of entries range from brief definitions of a few lines to expository discussions of serious lengths. The aim of this encyclopaedia is to satisfy the immediate technical needs of the user. E-commerce is presented as a unified, ever-growing, and stimulating body of knowledge. In terms of its broader objectives, the present book may be viewed as an outline or compendium of e-commerce ideas correlated with a large collection of specialized items.