Sancho Panza is a perfect example of the “picaresque” character in literature, harkening all the way back to Greek and Roman comedy, through Moliere, up to the “sidekick” tradition of movie Westerns.  He is the wily slave, the master of his master, who acts like the servant or lackey but in fact has the measure of the “master” (in this case Don Quixote) because he knows his master’s weaknesses and imperfections, understands his master’s need for fame or class or recognition, and whose native with and “street smarts” allows him to function well in the hypocritical world he finds himself in. In The Servant of Two Masters, for example, the comedy is derived from the servant exploiting two masters at once, playing one against the other.  The character gets its name from Lazarillo’s novel Picaro (Spanish for "scoundrel") (1554), perhaps the best full-length portrait of this staple of comedy.Other famous characters in this genre are Til Eulenspiegel and Huck Finn.