Charles Darwin did not invent anything but he discovered a lot as a scientist and naturalist; and, as an author, he impacted science and the way we think about our world. He developed and proposed a theory about evolution. His theory has had far-reaching affects on science and the way we understand life.
In a time when easy word processing has allowed for typeface styles such as italics to be easily incorporated into text, the importance of underlined (or underscored) text has been greatly diminished. Underlined text is often used in the middle of sentences indiscriminately as a way of providing emphasis, sometimes in superfluous addition to italics and boldface. Even when a discerning individual attempts to use the underscore correctly, he or she often ends up applying the attribute to a word or phrase that does not require an underline. Learn when to underline and the simple rules of underlining words.