diff --git a/README.md b/README.md
index 4cfc35341a7d8a12f00095ec5d127b4e85248c55..d4539bc2c9d865ba39f9f8f775d0efc04a95e36a 100644
--- a/README.md
+++ b/README.md
@@ -10,6 +10,11 @@ However, if you want to make game in modile environment not using mobile web bro
  <strong>Phaser API docs</strong>: https://photonstorm.github.io/phaser3-docs/index.html <br/>
  <strong>Phaser Examples</strong>: https://phaser.io/examples <br/>
 <br/>
+# Why Phaser?
+You many wonder why i talk about **Phaser** instead of **Unity** or other game engines. Here are some reasons why people use Phaser.<br>
+* Using Phaser, you can make single game working on both Desktop and Mobile easily<br/>
+* This is Open Source Framework so you can use it freely and contribute to **[Phaser GitHub](https://github.com/photonstorm/phaser)** to improve it
+* Unless you use third party app or other frameworks, only you need to run Phaser game is web browser like chrome or safariw
 # How to prepare for using Phaser?
 ## Before prepare for phaser
 Before prepare for using Phaser, you may need local webserver to run Phaser game because of security issue or CORS problem. In that case, prepare your favorite local webserver environment.
diff --git a/lifecycle/README.md b/lifecycle/README.md
index 28a0b3bda0b6cc240c28014b268bbb8f48d2556e..3145a74a6191d7814dc9589974443f64c5c43b0d 100644
--- a/lifecycle/README.md
+++ b/lifecycle/README.md
@@ -23,3 +23,18 @@ Usually, you can load images or other resources at **preload** and create Phaser
 ## Why we load resources at **preload** and make objects at **create**?
 You may wonder why i suggest you to load resources at **preload** and create objects at **create**. Well, if you try you may see that some objects not being created well especially image related objects. This is because Phaser is based on JavaScript which makes loading resources asynchronously. Thus, to avoid such problem, i recommend you to load resources at preload and create phaser object at **create** but it is not mandatory nor official.
 
+ ---
+## How can i change update rate?
+You may want to limi your update rate because of performance issue or other reason. And you can limit them since start by setting **config** for physics or using **physics.world.setFPS()** but it sometimes doesn't work depends on your Phaser version. Then, how should you do to do so? You can limit update rate by skipping some of update execution. Below is example
+<pre><code>
+    function update(){
+        this.c += 1;
+        if(this.c > 1){
+            this.c = 0;
+            return;
+        }
+        ...
+    }
+
+</code></pre>
+Above code would let Phaser run **update** as half of default rate whcih means, if your Phaser game execute **update** 60 times a second, then above code block will make it 30 time a second.
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diff --git a/physics/README.md b/physics/README.md
index 96cc137b727edd7e0b65764c71c58cc50e71d775..1035b54824fba3728e45d642575e5fcae9b56c09 100644
--- a/physics/README.md
+++ b/physics/README.md
@@ -11,4 +11,4 @@ If you searched about it before, then you would see many comments saying that **
 From above, you may think 'why should we even consider about **matter** while it just wastes more memory thatn **arcade**?'. One of ther answer is that **matter** has more natural physic engine than **arcade** like complex shapes or chain of bodies. So, if you try to make game with high-level physics, you should use **matter** or mix it with **arcade**
 
 ---
-## Examples of Phaser physics
\ No newline at end of file
+## Examples of Phaser physics