: A function is "pure" if it always gives the same output for the same input and has no side effects (it doesn't change anything outside itself, like updating a database).
: You focus on the logic of what needs to be solved rather than the specific control flow (like for or while loops). Why Bother Learning It? Functional Programming For Dummies
: Once you create a piece of data, you never change it. If you need a modified version, you create a whole new copy with the changes. : A function is "pure" if it always
: In FP, functions are treated like any other variable. You can pass them as arguments to other functions or return them as results. Functional Programming For Dummies