Mukta Balti. UTC - Universal Time Co-ordinated

Notation

• The international standard date notation is:
  YYYY-MM-DD (e.g. 2002-12-25 (i.e. 2002-December-25)).
• The international standard time of day notation is:
  hh:mm:ss (e.g. 23:59:59).

Time Zone

Without any further additions, a date and time as written above is assumed to be in some local (possibly unknown) time zone. The suffix 'UTC' indicates that a time is measured in Universal Time Coordinated:
2002-12-25 23:59:59 UTC

Since the introduction of an international atomic time scale in 1972, almost all existing civil time zones are now related to UTC. Where GMT is quoted, this in fact refers to UTC.

Why bother?

Using a standard time notation, allows anyone in the world to know exactly what your time means, relative to, and regardless of, where they are in the world. This is important because not everyone, who has access to a web site, is living in the same month, year or even the same century as the web site location.