Computer E commerce in Rex is a growing sector with a number of companies seeking to take advantage of the rising demand for online purchases. E-commerce refers to business over the internet, and it operates in four of the major market segments: business to business, business to consumer, consumer to consumer and consumer to business. E-commerce relies on applications that are dependent on the internet such as web services, instant messaging, shopping carts, and e-mail, among others. This business has several advantages such as convenience, selection and competitive priced items. Robust software and reliable software are important for a successful computer E commerce.