Add related to topic "Functional programming"

Author: shaedrich

topics/functional-programming/index.md

@@ -3,6 +3,7 @@ display_name: Functional programming
 short_description: Functional programming is a programming paradigm where programs are constructed by applying and composing functions.
 topic: functional-programming
 wikipedia_url: https://en.wikipedia.org/wiki/Functional_programming
+related: oop, declarative-programming, procedural-programming, event-driven-programming
 ---
 
-In computer science, functional programming is a programming paradigm where programs are constructed by applying and composing functions. It is a declarative programming paradigm in which function definitions are trees of expressions that map values to other values, rather than a sequence of imperative statements which update the running state of the program.
+In computer science, **functional programming** is a programming paradigm where programs are constructed by applying and composing functions. It is a declarative programming paradigm in which function definitions are trees of expressions that map values to other values, rather than a sequence of imperative statements which update the running state of the program.