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

Chat technical support is a form of technical support delivered via online chat. Online chat refers to a kind of communication over the Internet that offers an real-time direct transmission of text-based messages from sender to receiver. wikipedia.org

A help desk is an information and assistance resource that troubleshoots problems with computers or similar products. Corporations often provide help desk support to their customers via a toll-free number, website and e-mail.

Customer support is a range of customer services to assist customers in making cost effective and correct use of a product. It includes assistance in planning, installation, training, trouble shooting, maintenance, upgrading, and disposal of a product. wikipedia.org