Fundamental operation on lists.
Similar in some ways to * for numbers
You can't really get good at list processing without using map. Looping instead of using map is sort of like doing repeated adds in a loop instead of using multiplication with integers.
Transform one list into another.
Keep this in mind every time you use map. If you are not really doing a transform, then map is the wrong tool.
my @minutes = map { int( $_/60 ) } @seconds;
Simple transformation from an array of seconds into an array of minutes.
my @dts = map { DateTime->from_epoch( epoch => $_ ) }
@unix_times;
The last example wasn't very likely to ever be really useful, but this is something that you might actually imagine doing. I have a list of Unix epoch times, but I want DateTime objects, so...
Turn the whole idea inside out: summary.pl.
I would never do this in production code, because the other developers would probably find it hard to follow. In this case, I'm processing a piece of data with an array of code references, to generate summary information about the data.