Anyone care to tell me what the difference is between the term `Time` and `CPU`?

Anyone care to tell me what the difference is between the term `Time` and `CPU`?
 > Benchmark                                         Time             CPU           Iterations
> -----------------------------------------------------------------------------------------
> BM_Original                                    105 ns           105 ns        6975724
> BM_Alternative                               97.5 ns          97.4 ns       7628098
> BM_Alternative/threads:100         *1.80 ns*          *176 ns*        3962100

Where can I see the definition of them? It seems a bit difficult for me to find some _manual_ in that regard.
(I mean why is `CPU` higher than `Time`? :confused:) (edited)