The name Charles (or Karl) is Germanic in origin. It means "free man." In Middle English the word "carl" (now often used as a name) or "churl" (Old English "ceorl") was still being used to denote a freeman, one step above the serfs but with little status; the word "churlish" derives from this. The name Karl has been popular in Germany since the days of Charlemagne (in Latin Carolus Magnus, or "Charles the Great.") It spread into England largely because it was the first name of King James 1, who came to the throne in 1603 (James had been brought up in France and was partly French.)
Charles is often shortened to Charlie or Chas (occasionally, in North America, Chuck.) Female equivalents include Charlotte, Carla, Carlotta (rare in English-speaking countries) and Carly, as in Carly Simon. Derived from the Latin form of Charles, Carolus, there are also the female variants Caroline, Carol and Carola. These are often shortened to Carrie, Callie and (formerly) Caro.
Charles is often shortened to Charlie or Chas (occasionally, in North America, Chuck.) Female equivalents include Charlotte, Carla, Carlotta (rare in English-speaking countries) and Carly, as in Carly Simon. Derived from the Latin form of Charles, Carolus, there are also the female variants Caroline, Carol and Carola. These are often shortened to Carrie, Callie and (formerly) Caro.