Humans have always been fascinated by time and have expended enormous energies inventing ways to understand it and measure it, but time, by its very nature, is a fickle and changeable thing.
From nanoseconds to millennia and beyond we measure it, lose it, find it, spend it, save it, waste it, and are preoccupied with its use but there never seems to be enough of it. Unless you are a five year old child, in which case there seems to be an inordinately large amount of it between Christmases or birthdays.
Interestingly enough, as we experience more time it seems to condense - a year when you are 5 is an eternity but at 50 that same time passes incredibly quickly and birthdays seem to occur at shorter and shorter intervals. Similarly, why, when travelling, does it take longer to arrive at a destination than it does to return from it? Is time the variable, or distance? Why is the time between annual holidays so long and yet annual visits to the dentist come round so quickly? Two hours spent in the company of those boring relatives is very different from two hours with that scintillatingly intelligent person who appreciates your wit.
Do different entities perceive time differently? Does an insect whose life span may be only 12 hours sense an hour in the same way as a cockatoo with a 100 year life expectancy? If not, if time is all about how much of our life is passing, what does that do to the human way of measuring time and what are we measuring anyway?
Time is inconstant and constantly mutating. It has many forms, among them - "Net time" compresses hours into minutes, "waiting time" stretches minutes into hours and "spare time" is always there but never happens.
Time can be active or passive - it flies, drags, runs out, passes, it can be taken, kept, lost, used, even killed - but no matter what we do to it or with it, it goes on – and on and on and on.
Thank goodness there are always better times ahead.