Different cultures around the world record time in different fashions.According to the Gregorian calendar, it is the year 2009 AD. The Kaliyuga Hindu Calendar maintains it is 5110, the Islamic calendar 1430 and the Persian, 2630.Plants and animals naturally incorporate both the abundant C-12 isotope and the much rarer radiocarbon isotope into their tissues in about the same proportions as the two occur in the atmosphere during their lifetimes.When a creature dies, it ceases to consume more radiocarbon while the C-14 already in its body continues to decay back into nitrogen.Chances are, right now, you have a Gregorian calendar stuck to your wall.
The period of time that it takes for half of a sample to decay is called a "half-life." Radiocarbon oxidizes (that is, it combines with oxygen) and enters the biosphere through natural processes like breathing and eating.
Radiocarbon dating is one of the best known archaeological dating techniques available to scientists, and the many people in the general public have at least heard of it.
But there are many misconceptions about how radiocarbon works and how reliable a technique it is.
It was the first absolute scientific method ever invented: that is to say, the technique was the first to allow a researcher to determine how long ago an organic object died, whether it is in context or not.
Shy of a date stamp on an object, it is still the best and most accurate of dating techniques devised.