[racket] Newbie question about local

(define (g)
  (define (f x) (* x x))
  (f 2))

(define (h)
  (local [(define (f x) (* x x))]
    (f 2)))


Both functions above work fine.

Could anybody tell me what the difference is between those two
functions where in one case I use local and in the other case I omit
local?



-- 
Thanks,
Manfred