From cac94a4f1d278e5239b216618f8c96441d9bd970 Mon Sep 17 00:00:00 2001
From: "hemanth.hm" <hemanth.hm@gmail.com>
Date: Sun, 7 Jun 2015 18:20:10 +0530
Subject: [PATCH] Defined side effects.

^
---
 readme.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/readme.md b/readme.md
index 0333e14..14f9f78 100644
--- a/readme.md
+++ b/readme.md
@@ -73,7 +73,11 @@ greet // yo;
 ---
 
 ## Side effects
+> A function or expression is said to have a side effect if apart from returning a value, it modifies some state or has an observable interaction with external functions.
 
+```js
+console.log("IO is a side effect!");
+```
 ---
 
 ## Idempotency