time

Time is the dimension that is characterized by sequences of events. In physics it is seen as a 4th dimension. A Space-time diagram shows the relationship between space and time with time as a 4th dimension. It is unique in that we only travel through time one way. (forward). Time is one of the three main parts of the Universe: space, time and mass. Relativity shows them to be inter-related with space and time are so interrelated that they form a single entity. Mass warps space-time forming gravity and motion of mass contracts both space and time.