The word "while" is a conjunction used to indicate that two actions or events are happening at the same time. For example, you might say, "I listen to music while I study." In this sentence, the use of "while" shows that both activities occur simultaneously. Additionally, "while" can also introduce a contrast between two ideas. For instance, "While cats are independent, dogs often seek companionship." Here, "while" highlights the difference in behavior between the two animals. This dual function makes "while" a versatile word in English grammar.