I find them very useful in the way Racket uses them, which is by convention only. In Racket, `[<expression>]` is identical to `(<expression>)`. But Racket uses

I find them very useful in the way Racket uses them, which is by convention only. In Racket, `[<expression>]` is identical to `(<expression>)`. But Racket uses them in a conventional sense, for example, in `let` bindings: (define test (let ([a 1] [b 2]) (+ a b)))