  While there is no consensus about the history of time since the beginning, in
this paper I will discuss some possibilities. We have a pretty clear picture of
cosmic history from the electroweak phase transition through the time of
recombination, a period which includes the QCD phase transition and big bang
nucleosynthesis. This paper includes a quantitative discussion of the age of
the universe, of the radiation-matter transition, and of hydrogen
recombination. There is much evidence that at earlier times the universe
underwent inflation, but the details of how and when inflation happened are
still far from certain. There is even more uncertainty about what happened
before inflation, and how inflation began. I will describe the possibility of
``eternal'' inflation, which proposes that our universe evolved from an
infinite tree of inflationary spacetime. Most likely, however, inflation can be
eternal only into the future, but still must have a beginning.
