I18n = Internationalization

I18n stands for "Internationalization"

The story goes as follows (as sited in Internet):
A DEC employee named Jan Scherpenhuizen was given an email account of S12n by a system administrator, since his name was too long to be an account name. This approach to abbreviating long names was intended to be humorous and became generalized at DEC. The convention was applied to "internationalization" at DEC which was using the numeronym by 1985.