The modern English calendar has been the bane of many a software designer. Our system of
  keeping time consists of months of varying lengths, leap years, and sometimes leap seconds. There
  are 52 weeks and 1 day in a year, except for leap years of course. Then there is daylight savings
  time, which may or may not be followed in some states and countries. Plus, how many of you
  know or even care, that way back in 1752, September had only 18 days? Such inconsistencies
  can drive programmers to the brink of insanity.
  Computer calculations involving dates and times are notoriously difficult to verify fully.
  Unfortunately, date/time glitches occur all too often in the computer industry. It is not unusual for a
  large corporation to have a program, which has been working fine for years, all of a sudden go
  crazy because of a date/time related bug. These things happen all the time!
  One such bug is now creating a worldwide hysteria. It is filling corporate America with dread even
  as a whole new mini industry forms around it. This problem must be big; it even has its own catchy
  sounding acronym: Y2K. More formally, this is known as the "Year 2000 problem."
  As the story goes, because programmers have used the last two digits of the year to store data,
  computers may not be able to tell the difference between the years 2000 and 1900, or 2001 and
  1901, causing them figuratively to spark and blow up. Apocalyptic stories abound from the
  ridiculous to the not-so-ridiculous. Airliners could be grounded because their maintenance is 99
  days overdue. Elevators will grind to a halt. Senior citizens will be sent to pediatric hospitals
  because the computer thinks they are children. And phone bills may not be received on time. The
  common theme is that the safe world we humans have created for ourselves shall turn to chaos.
  Confusion reigns supreme on Y2K, so allow me to dispel a few common myths:
  Myth #1: "There is just one Y2K problem."
  Reality: There are a multitude of problems which must all be approached differently.
  Myth #2: "The Y2K problems will not occur until the year 2000."
  Reality: We are seeing it now in programs which must compute dates in the future. Calculations
  involving loans over 3 years, and calculations involving retirement funds for 20 year olds when they
  turn 65 are just a few examples. Also, a computer has already sent a 104-year-old patient to a
  pediatric physician.
  Myth #3. "There are software products on the market which will automatically detect Y2K
  problems and fix them."
  Reality: Yes and no. Yes these products exist, but they are tools which merely help fix some very
  specific Y2K problems. You see, there are many different types of computers, operating systems,
  languages and applications involved here. No single Y2K product is going to solve all of them and
  each of these products can only address a very narrow range of issues in specific computer
  environments. Even then, not all bugs may be found. The only surefire methodology is for a human
  being to look at the programs manually and fix them. This grunt-and-sweat approach is at odds
  with the gee whiz "put the program in an oven and wait 5 minutes" approach being espoused by
  some hypesters out to make a buck off this hysteria.
  But the truth does not stop expensive consulting companies from charging for "studies." It doesn't
  stop companies from hyping products of dubious merit, and it doesn't stop Wall Street from
  pumping up the stocks of those companies in a perceived market which may not be as big as some
  pundits have said. The Gartner group has estimated that this is a $600 billion problem. Some other
  estimates say $500 billion. These figures are the size of the Gross National Products of some small
  nations! Pardon me for being a skeptic, but do these numbers sound reasonable to anyone from
  this solar system?
  A Y2K apocalypse is scary stuff; can the doomsayers be right? The answer is "yes," but only if
  nothing is done about it. And therein lies an interesting paradox. The Y2K problems are so drilled
  into computer professionals' minds that they are already being addressed. They are disappearing
  one by one. Because it exists, the hysteria is fixing itself. You may want to read that last sentence
  twice. Okay, maybe three times. A few isolated Y2K problems are bound to occur here and
  there, but a disaster of global proportions seems rather far-fetched.
  Now, let me propose a real heresy to the Y2K zealots. The market for Y2K products may be
  shrinking instead of increasing. Think about it. Y2K problems have already been seen in some
  organizations and have been solved. Other companies have been quietly phasing in Y2K compliant
  software on their own for the last several years while others are getting started as I write this. Yes,
  there are a few niches here and there, but combine the above facts with the 3- to 4-year shelf life
  of many of these products and the future does not look so bright for the Y2K industry.
  I don't know what it is about millennia. During the last millennial change, predictions about the end
  of the world ran rampant through medieval Europe. Yet despite the ugly aftermath from the fall of
  the Roman empire, the Black plague, and Barry Manilow, the last thousand years turned out pretty
  darned well. Don't be fooled this time. Despite the doom-sayers, the next millennium ought to be a
  humdinger. That is, of course, until the English crop circles are properly decoded, prompting aliens
  to wage an all out assault on our planet as predicted by Nostradamus.
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