what does index do in arrays?

[soulgnat]

what does index do in arrays?
for example

index ("aeiou", s(1))

what is index used for?

and what does this do?

setscreen ("fill:3")

[Tony]

index() is used to search for substrings in a string. Has nothing to do with arrays.

setscreen() is used to format the output screen. Usually used to change the window size and to go into "offscreenonly" mode