Survival analysis is a branch of statistics that deals with analyzing the time until an event of interest occurs. It is commonly used in medical research, engineering, finance, and other fields to study the probability of survival over time, taking into account various factors that may influence the outcome. Survival analysis involves estimating survival curves, hazard functions, and other statistical measures to better understand the factors that affect the timing of events. It is often used to study medical outcomes such as patient survival rates, disease progression, and treatment effectiveness.