Kline Felter Syndrome is a genetic disorder where males are born with an extra X chromosome, resulting in XXY sex chromosomes. It occurs due to a random error in the mother and father's sex cells when the baby is conceived. Signs include a taller and less muscular body type, broader hips, larger breasts, weaker bones, and smaller genitals. It can cause learning problems and issues with sexual development or infertility. While there is no cure, treatments can help address symptoms.