Emma, along with her brother John, grew up working in the family business, which is where she probably learned her bookkeeping skills.

Painter, who was a relative of Hunter, taught her the basics of telegraphy and recommended her hire by the Atlantic and Ohio Telegraph Company (which later became Western Union).

[2] We remember well that the wires were introduced into a neat sitting room of a home in Westchester [sic], Pa., where, with the instrument on one side and a work basket on the other, our new assistant sent and received her messages, and filled up the interim in fixing her Sunday bonnet, or embroidering articles of raiment which a gentleman editor is not expected to know or name.Using the telegraphic pseudonym (known as a sine) "Emma of S," Hunter quickly gained a reputation in the company as one of their most capable telegraphers.

As the lines grew busier and the social stigma of being a female telegrapher faded, in 1857, Hunter moved her office to her mother's store.

[9][2] Thomas Jepsen, a writer who focuses on the history of technology,[10] has argued that she was the world's earliest electronic commuter, as she worked from her home to send and receive telegraph messages and keep the company's books.