Your persona is the public image you present to the world. When T.S. Eliot wrote in "The Love Song of J. Alfred Prufrock" about preparing "a face to meet the faces that you meet," he had the persona in mind.
In ancient Latin the word persona meant "mask." The word also can refer to a character played by an actor. While a persona is not considered a lie or a falsehood, its meaning implies that it is only part of the truth. Like all masks, there is "real" person beneath. Often a performer will take on a persona to express certain parts of himself: the rapper Eminem also goes by the name Slim Shady to express his darker self.