Office administration is a set of day-to-day activities related to financial planning, billing and recordkeeping, personnel, and physical distribution and logistics, within an organization. wikipedia.org

Data mining is the process of discovering new patterns from large data sets involving methods at the intersection of artificial intelligence, machine learning, statistics and database systems. wikipedia.org

eBay.com is an online auction and shopping website in which people and businesses buy and sell a broad variety of goods and services worldwide.

Customer service is the provision of service to customers before, during and after a purchase. wikipedia.org

A data entry clerk, sometimes called a typist, is a member of staff employed to type data into a database using a keyboard. The keyboards used can often have specialist keys and multiple colours to help them in the task and speed up the work. wikipedia.org