Time, time, time

Time does squish through my fingers. Not only in the sense that time is always flowing, but more fundamentally, time can't be pinned down in its nature at all. Does it really flow like a river? Is it linear? Cyclical? What about memory - some things seem so, so distant in memory, yet near in time; others, so near, but long ago.

Twenty years ago, I couldn't grasp the concept of being alive 20 years into the future. But here I am - 44 years old today. Will I be alive in another 20 years - at age 64?

Is Time a place, a process, a primary or derivative phenomena?