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Two foundational typeclasses for converting between values and their textual form:

show 42        -- "42"
show 3.14      -- "3.14"
show [1,2,3]   -- "[1,2,3]"
show True      -- "True"

(read "42" :: Int)         -- 42 — explicit target type
(read "3.14" :: Double)    -- 3.14

show converts ANY Show-able value to a String. Use it for debugging or when you need a generic textual representation.

read parses — but you usually need a type annotation, since read "42" could plausibly produce Int, Integer, Double, etc. read THROWS on parse failure; the safe variant is readMaybe :: String -> Maybe a from Text.Read.

For IO, print is putStrLn . show — it shows then prints:

print 42         -- 42
print [1,2,3]    -- [1,2,3]