A Markov chain is a stochastic process that evolves over time through a sequence of states, where the probability of transitioning from one state to another depends only on the current state and not on the past history of states. In other words, it follows the Markov property, which is often summarized as "the future is independent of the past given the present." Markov chains are widely used to model various phenomena in fields such as probability theory, statistics, physics, biology, economics, and computer science.