Go to content Go to menu

Let this quote explain:

In Fortran, all variables starting with the letters I, J, K, L, M and N are integers... (This is the source of the long tradition of using "i", "j", "k" etc as the loop indexes of "for loops" in many programming languages -- few of which have implicit typing).

Wikipedia - Sigil (computer programming)

I guess you learn something new everyday.