Rev.13:18 Here is wisdom. Let him that hath understanding count the number of the beast: for it is the number of a man; and his number [is] Six hundred threescore [and] six - 666

A "score" equates to 20, therefore "threescore" is 60. Six hundred plus threescore plus six is therefore the number six hundred and sixty six.

The number 666 indicates that the letters in the Greek form of the name of the Antichrist will add up to 666. There is a slim possibility that his name will equal 666 in the Hebrew language since the Antichrist will be Jewish. The numeric system does not work in English or in languages other than Greek or Hebrew, so it is useless to calculate the values of names in these modern languages. (Grant R. Jeffrey, Prince of Darkness, 1994, pp. 275, 277)

Revelation also alludes to the fact that mankind will "wear the mark of the devil", and this has been taken as meaning a barcode or microscopic chip under the skin on the hand or forehead. Whilst this is not far removed from fiction today, there is still much scepticism over what form this will take, and how it relates to the number 666. Some say not to take the number literally, and that 666 refers to 6, 3 times. For example, a six digit number, starting with a 6, and printed in a 6pt font. Others do take it literally, and state that it will most probably be something like your Social Security Number, and this will start with the number 666 - although this doesn’t quite work for countries that don’t have a Social Security Number.

While people argue the meaning of the number, the possibilities of mankind being enslaved by wearing this mark, we plod on with our existence, knowing full well that there is not much we can do about it. Suffice to say, if somebody walks up to you with a laser tattoo device, or a syringe with a microscopic chip, don’t let them near your hands or forehead.