The Kaplan-Meier estimator estimates the distribution function of a lifetime T based on a sample of randomly right censored observations. In survival analysis the lifetime T is a nonnegative random variable describing the time until a certain event of interest happens. In medical applications examples of such events are the time till death of a patient suffering from a specific disease, the time till recovery of a disease after the start of the treatment, or the time till remission after the curing of a patient.