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

Typing is the process of writing or inputting text by pressing keys on a typewriter, keyboard, cell phone, or a calculator wikipedia.org

Subject indexing is the act of describing or classifying a document by index terms or other symbols in order to indicate what the document is about, to summarize its content or to increase its findability.

Proofreading (also proof-reading) is the reading of a galley proof or computer monitor to detect and correct production-errors of text or art. Proofreaders are expected to be consistently accurate by default because they occupy the last stage of typographic production before publication. wikipedia.org