Update _overviews/scala3-book/fp-pure-functions.md

Co-authored-by: Jonathan <jonathan@b-studios.de>

Author: alvinj

_overviews/scala3-book/fp-pure-functions.md

@@ -110,8 +110,8 @@ If you understand that code, you’ll see that it meets the pure function defini
 
 The first key point of this section is the definition of a pure function:
 
-> A _pure function_ is a function that depends only on its declared inputs and its internal algorithm to produce its output.
-> It does not read any other values from “the outside world”---the world outside of the function’s scope---and it doesn’t modify any values in the outside world.
+> A _pure function_ is a function that depends only on its declared inputs and its implementation to produce its output.
+> It only computes its output and does not depend on or modify the outside world.
 
 A second key point is that every real-world application interacts with the outside world.
 Therefore, a simplified way to think about functional programs is that they consist of a core of pure functions that are wrapped with other functions that interact with the outside world.