Entailment is a logical relationship between statements where the truth of one statement guarantees the truth of another. For example, if we say "All birds can fly," it entails that "Some birds can fly." If the first statement is true, the second must also be true. In formal logic, entailment is often represented using symbols. It is crucial in fields like philosophy, linguistics, and computer science, particularly in areas such as natural language processing and artificial intelligence. Understanding entailment helps in reasoning and making inferences based on given information.