map -package:conduit -is:exact -package:case-insensitive -package:bytestring -package:base-prelude -package:base-compat -package:amazonka-core -package:insert-ordered-containers is:exact -package:basement -package:Cabal-syntax package:pipes

Apply a function to all values flowing downstream
map id = cat

map (g . f) = map f >-> map g