Philadelphia chemist Robert Cornelius took what is widely believed to be the first “selfie,” in the back of his family shop, by removing the camera lens cap, running into the frame, and then replacing the lens cap. On the back of the photograph he wrote, “The first light picture ever taken. 1839.” Three-quarters of a century later, Russia’s grand duchess Anastasiya Nikolayevna took a series of self-portraits, steadying herself on the back of a chair. “I took this picture of myself looking in the mirror,” she wrote in 1914, four years before her execution. “It was very hard, as my hands were trembling.”

Thomas Edison is popularly credited with initiating the practice of saying “Hello” when answering the telephone. His rival Alexander Graham Bell preferred “Ahoy” (as used on ships) as a phone greeting and used it for the rest of his life. The first phone book, published in 1878, instructed users to begin conversations with “a firm and cheery ‘Hulloa.’ ” (To end conversations, it recommended “That is all.”) By 1889 telephone-exchange operators were known as “hello girls.”