we are used to using 3 + 5 if we add two numbers
Clojure is different from what we are familiar with.
(+ 2 3) this is clojure add form.
if we add numbers not only two, code will be complicated
ex) add(add(add(2, 3),5),6)
clojure is so simple
(+ 2 3 5 6)
and result is the same