2000 reasons to be careful

Computer users are always alert to the threat of "viruses", sophisticated codes which turn into ferocious eaters of software once they surreptitiously gain access to a system. Of late, however, they are finding a simple little beast - the Y2K bug - equally perturbing. A bug is usually regarded as an electronic problem caused by a "local error" in a computer programme - as distinct from a system-design error. The Y2K variety may be an unsophisticated trigger of computer glitches but has the ability to bring the most powerful technology of the 20th century to an abrupt halt. That is not to mention the risk of many systems failing simultaneously. Even back-up systems are threatened. Nor is it only a computer problem only. Many devices with in-built electronic timers may be affected.

Briefly, this is a date-reading problem arising from the almost universal practice of using shorthand to describe the year, for example 1998 is commonly referred to as '98. As a result, systems using two digits rather than four for the year may have problems counting days following December 31st, 1999. Some will halt, rejecting the notion of a year '00 and others read 01/01/00 as January 1st, 1900, which may result in erroneous commands. The nature of the year 2000 problem means any programmable electronic system may fail and so render inadequate safety arrangements dependent on the equipment. Systems may fail or give incorrect information. Results of calculations may be inaccurate, and may cause computer operators to take inappropriate action.

Problems can be hidden away in "embedded systems", which usually comprise some type of microprocessor or digital electronics - often with a timer - that are built into modern equipment such as instruments, machinery, sophisticated fridges, fire alarms and lifts to mention but a few.

As if problems surrounding January 1st next were not enough, they may go beyond the day 1999 become 2000. Other dates have the ability to cause similar "date-discontinuity" problems. These occur when the time - as expressed by a computer system or its software - does not successfully move forward with true time; for instance, a computer system which has not been programmed to recognise 2000 as a leap year. Dates to watch out for are: September 9th 1999; February 29th 2000, March 1st 2000, December 31st 2000 and January 1st 2001.

There are those who believe the first second of 2000 will trigger a worldwide computer crash and are already stocking-up on food, fuel and candles, with water tanks at hand, in a new embracing of self-sufficiency. Less panicky types are planning not to be technologically challenged shortly after midnight, or not to be technology-dependent just at that point, just in case.

Y2K does not, however, mean doomsday as it is possible to check for Y2K compliance using reliable testing procedures. Big corporations and utilities are already on the job. Smaller businesses and service providers seem less up to speed. Therefore, for many it may be a matter tottering into the new millennium.