Little in the computer world has caused more speculation in recent months than the so-called "millennium bug".
This is the name given to the problem caused by hardware and software which use only the last two digits of the year rather than all four. Essential computer systems could be vulnerable when they tick over from "99" to "00" - making some of them interpret the year as 1900.
Estimates of the damage that could be caused range from global meltdown to minor irritation. Some people have gone as far as to take measures to prepare themselves for the collapse of civilisation. You can express your opinion on our Y2K Talking Point.
BBC News Online has collected facts and figures both from around the globe and on essential parts of the UK infrastructure.
If you are wondering what all the fuss is about, or want to know what is being done about it, take a tour of the world via our clickable map. For a detailed look at how the millennium bug might find its way into the homes of UK residents, follow the link to Bugtown UK.
The UK Government's Foreign and Commonwealth Office has collected information about the state of preparedness of many countries.