An e-tailer is online retailer who leverages the efficiency of the Internet to improve a customer's buying experience. Advantages of e-tailing over traditional retailing include 24/7 availability, searchable product offerings, low overhead, and detailed product descriptions.

There are two distinct types of e-tailers: pure e-tailers and mixed e-tailers. Pure e-tailers operate entirely online, such as amazon.com Mixed e-tailers (also known as "click-and-mortar") retailers who use online and "brick-and-mortar" channels to increase their customer base. An example of a mixed e-tailer is Barnes & Noble Booksellers.