‘How does time pass?’ considers the concept of time — what it is and how it is measured. Could there be time without change? Philosophers have debated two models of time. The first tries to explain the passage of time in terms of events and things having a property of presentness, pastness, or possibly futurity. The second says that the events and things in our world stand in relations of order to each other; they are temporally related and to that extent can stand in a sequence. Is time a single straight line? Is it a finite resource? The debate continues.