- year, in two-digit, numeric format, as in: dd/mm/yy
yy - Computer Definition
Abbreviation for the two-digit storage and display of a year, as in 07. Older computer systems stored dates in the format xx/xx/yy, which represents variously represents month/day/year or day/month/year, depending on whether one is using the American system or the little-endian notation used in most of the rest of the world. In either case, before the year 2000 (Y2K), the possibility existed that a two-digit date would be interpreted as 1900 and disrupt the operation of older computers that the manufacturers had fully expected would be replaced long before 00 became an issue. See little-endian.