Classics and Historical Figures:
* George Eliot: Mary Ann Evans
* Mark Twain: Samuel Clemens
* Lewis Carroll: Charles Lutwidge Dodgson
* J.K. Rowling: Joanne Rowling (though she used her initials for a while, she later legally changed her name to J.K. Rowling)
* Voltaire: François-Marie Arouet
* Currer Bell: Charlotte Brontë
* Ellis Bell: Emily Brontë
* Acton Bell: Anne Brontë
* Ouida: Marie Louise de la Ramée
* L. Frank Baum: Lyman Frank Baum
* Stephen King: Richard Bachman (for horror novels)
* Benjamin Franklin: Richard Saunders (for Poor Richard's Almanack)
Modern & Contemporary:
* J.D. Robb: Nora Roberts
* Robert Galbraith: J.K. Rowling
* Richelle Mead: Richelle (she uses her first name for her adult romance novels)
* A.J. Finn: Dan Mallory
* R. Eric Thomas: Eric Thomas
* Ashley Winstead: Ashley Winstead (she uses her real name for her adult contemporary romances and a pseudonym for her historical romances)
* J.R. Ward: Jennifer Rardin (she uses her initials and middle name for her Black Dagger Brotherhood series)
Reasons for Using Pseudonyms:
* Gender: Some authors, particularly female authors in the past, used pseudonyms to avoid the gender bias in publishing.
* Genre: Some authors use pseudonyms to separate their work in different genres.
* Privacy: Some authors use pseudonyms to protect their privacy.
* Brand Building: Some authors use pseudonyms to establish a distinct brand for a particular type of work.
This list only scratches the surface! There are many more authors who have used pseudonyms throughout history.