Far more generations of humans grew up with no concept of time than have grown up with any concept of days of the week or months of the year.

Firmly in the "time = illusion" camp here. There is only now.

Time is definitely real. Other organisms also measure time--think circadian rhythms, migrations, and other time dependent events such as when to mate or when to store food, etc. Humans have only found a way to quantify time.
Also, side note: have you noticed how time seems to speed up as you age? Memories from my childhood seem to have lasted forever but the older I get the quicker the years seem to pass. I think this is due, at least in part, to perspective--as a child if you've only been alive for 5 years, 5 years seems like forever; but if you're 70 years old, 5 years may seem like no time at all.

Well yeah, but that's why we have precise measurement tools. 7 minutes is still 7 minutes, whether you're taking a nap or in a firefight. Much like how a like is still a mile wether your athletic and can run it in under 9 minutes without breaking a sweat or way out of shape and it takes you more than 30 and you pretty much feel like you're going to have a heart attack by the end. Time is real, even if our method of measurement is arbitrary.

Time is a real concept until space dies. Then time becomes an impossibility and an absolute.
When you remove time, all possibilities occur simultaneously. When you remove Space, Time is both infinite and non-existent.

When it all comes to an end all of it immediately exists. So carries the infinite cycle of regurgitation.

Time is infitine anyway, time is simply in the moment, what we live at this time
Sartre said 'The Past is the Future'

Einstein showed us that time is not anything like we think it is. It isn't unchanging but can be altered depending on how fast someone is going or how close they are to a gravitational source. I've always found relativity very interesting!

Well actually siderial time is a totes human construct based on the estimated time it takes the dirt to make a complete revolution around the sun.
Beyond our little neighborhood time isn't a single measurement, in fact it's part of space its self..as explained by Einstein in his theory of Special Relativity...hence the descriptive word Spacetime, or the bending of space and time due to the warping of it by both the gravitational influence of the mass of the sun And the mass of the earth combinded, or to shorten it..Entropy.

Time is an illusion and lunchtime doubly so.

Personaly, I don't believe in time, I use it to co-ordinate with people. but to me it is just another measure of space, a more encompassing one. To me a place in time is where every piece of the universe is in a certain place. I will meet you at x spot when all of these things are in these places, but to make it easier, we will use this device to estimate that and we will know.
Unless of course some of you are travelling close to the speed of light, then it won't work for you.
It doesn't work for me. Tis ok I know I am not making any sense, but the whole concept of time does not make sense to me. It is not a thing, it is not real, we just need it to create a sense of order in the universe that we can get our heads around.

Time is both real, and... not so much.

It is a construct that we humans devised to help us to understand things going on around us. It gives us the ability to reference things in the past, or future (something animals, some at least, can't do). It is a fascinating subject. The reality of which is, no, we really don't need it save to be able to have those discussions.

Having come up with time, and creating abilities to measure it that become more and more precise, we start to reference that even. Thus, back in the day, a morning meeting was just that, a meeting that occured sometime after you got out of bed, and before lunch, generally when the sun was about midway in it's path for the day. It wasn't 8 "o the clock" (which is where o'clock comes from) or anything that precise. Later, as clocks, and then watches, became more available, we started having meetings on the hour... eventually, we would have meetings at 8:10 precisely and be upset when someone didn't show up until 8:12.... all of which is, silly at best. It causes stress.

There actually is a movement (too quiet mind) to have 'slow' clocks and watches. Watches that do NOT have a minute hand (OR seconds hand!). The idea is to get back to a day in which it is OK to meet in the morning, possibly over coffe, and talk about what needed to be talked about in as imprecise a time frame as you wish. Rather than thinking that if the conversation lasts more than 7.2 minutes, something is wrong!

Back to science, all of the social parts said, time has been a winner for science. It's allowed us to measure light, and the speed thereof and come up with concepts such as you have mentioned. It allows us to get a precise relative speed to different objects and thus a precise understanding of which is approaching which, and how fast (or which is running away, and how fast).

But, in the end, as one of my favorite physics professors said "we are in charge" of how we set up and view the problems. We created time, we should use it to help, not to create stress. Sadly, we do too much of the latter, and not enough of the former.

Oh, as for why time goes slowly in the meeting? You are forced to pay attention to... nothing. Which is what most meetings (the ones I have been in, in a corporate environment), are full of, they are a means for management to 'hear', rather than experience, what their subordinates are doing... wouldn't it be so much better if they could put down their watches and choose to experience what their subordinates are doing so as to understand it and realize what the needs are and how significant the job is?

The times that fly by quickly? You are engaged in something which has your full attention and is worthy of that attention. Sure, this can be a game, or music, or a problem which entices you. Being focused on this and NOT on the clock, allows your sense of time to slip and... next thing you know you've been talking to that cute redhead for 6 hours! WOW! Heheh... we've all been there. Why not admit it?

STOP watching the clock, watch life instead.

It helps society function more efficiently.

Time is continious, one direction, it passes by, it is thought to have begun with a bang which expanded and continues to expand in space, time is closly identified with space with the thought that they may be fused

Psychological time can be quick or slow, intense or boring, it can be seasonal or cyclic. I think we talk of time passing because we have an ego, the self as the locus of unity, without such a 'stationary' point I doubt time's passing could be cohenently understood.

Time is an integral part of reality. Many physics equations incorporate time into the formula. The ability of those equations to predict real results is conclusive.

The Amondawa people of the Amazon have no watches or calendars and live their lives to the patterns of day and night and the rainy and dry seasons.They also have no age and mark the transition from childhood to adulthood to old age by changing their name.They have no words for week ,month ,year , minuets ,hours etc

Different perceptions of time by different people,

Time is only an illusion.
All time is really "now," the same as all energy is only one entity.

"For us believing physicists, the distinction between past, present and future is only a stubbornly persistent illusion." -Einstein.

Not really for instance your time in the usa is way different to mine and the first lights of fires etc from thousands of years ago are still traveling with the imaggise from that first light.

I always think if nothing was around to precieve time would time play a role.

Interesting that you would bring up this topic at this time. (ha ha ha) I have been pondering this alot lately. Specifically I've been considering how Einstein's theory of relativity figures into the whole concept of time. Some of the things I've read talk about how time probably isn't linear. However since as mere mortals we probably can't get our heads around the concept of non-linear time, I'll just have to accept it. According to some theories there seems to be the possibilty that time's flow can be changed. It's an interesting possibility and I look forward to looking into it further.

Well, I think time is real. I also think that time is as much an individual property as, say for examples, our hair colour, our DNA, our liking of one food over another.

As in Einstein's concept of time, if I travel for 5 years (of my time) away from Earth as close to the speed of light and 5 years (of my time) back, I would have aged only 10 years. While every one on Earth would have experienced 30 years of their own time. From my perspective, I had travelled 20 years into the future.

We each experience our own times relative to how fast we are moving. The faster you move, the slower your time.

Here is Brian Cox, a UK scientist, explaining time travel forward:

EDIT: To clarify, although I think time is an individual property - it actually is not. It is only an individual property to us as much as we experience. It is a simplication. Time itself is space - as in space-time. There is no separation of "space" (as in actual space that we occupy) and "time" (as in time that we experience). But that's a totally separate discussion.

One of the dimensions, as in space time. We only observe a moment in time, but our memories allow us to perceive time in sense. It's said that a Photon doesn't exist through time only as moments in time, when it is created and then when it arrives/is absorbed/perceived for it no time passed.

The further you look in the distance the further it is in the past. Seeing the sun might be 7 minutes ago in the sun's past, but looking at your hand in front of your face is obviously pretty immediate I've also heard people argue that time isn't real for some reason, it is, we have just found ways to measure it and track it, at least relative to us.

Perception.

I just made a post about time an hour ago. Soon it will show up.