In different parts of the world, the numerical date and time are written with the year, month, hours and minutes in different orders. Some may say 11/21/99 while some may write 99.21.11. There are localization parameters in operating systems to try to deal with these differences. However, these are all subject to misinterpretation. For example, can you tell the date by looking at "11.10.12"?
The only correct way to write all dates and times are to write them the same way we write numbers. The convention of writing numbers the same way everywhere. The most significant digit is on the left, and going right you see a progression to the least significant digit. This makes it easy to sort numbers by value.
Dates and times should be written this way as well, with the most significant part on the left, and least on the right:
So, be part of the high-IQ club, and start writing all of your dates sanely.
Written, 2001/11/21;13:12:14.000
P.S. Tragically, the computer industry was split by a similar problem known as the big and little endian byte ordering problem. From what I can tell, Intel and IBM were to blame here. They started by reversing the order of the hex digits within a byte in their 4 bit processor and continued this at the byte level into the next ones. IBM is to blame because of their endorsement of Intel's architecture in the IBM PC.