diff --git a/CONTRIBUTING.md b/CONTRIBUTING.ja.md
similarity index 100%
rename from CONTRIBUTING.md
rename to CONTRIBUTING.ja.md
diff --git a/README.md b/README.md
index d4ceccd..aac0fde 100644
--- a/README.md
+++ b/README.md
@@ -4,11 +4,11 @@
 
 [日本語のREADMEはここ](https://github.com/DeNA/PacketProxy/blob/master/README.ja.md)
 
-# PacketProxy
+# About PacketProxy
 
-PacketProxy is an open source proxy tool that allows TCP/UDP Traffic to be read. It is not limited to just HTTP.
+PacketProxy is an open-source proxy tool that can intercept and inspect any protocol over TCP/UDP, not limited to just HTTP/1.x, HTTP2, or HTTPS.
 
-It can be used for development assistance or for risk assessments.
+PacketProxy is designed for testing web applications for internal use, which helps app developments and finding vulnerabilities on your applications.
  
 # Screenshot
 
@@ -16,42 +16,39 @@ It can be used for development assistance or for risk assessments.
  
 # Features
  
-- **Full featured local proxy tool**
-  - Show all the received packets
-  - Filter/Search packets by keywords
-  - Intercept packets, and modify them before sending them to server
-  - Resend packet to server
+- **Full-featured local proxy tool**
+  - Save all captured packets (i.e., requests and responses) and show them in the history tab
+  - Filter/Search packets in the history tab (e.g. `requests==/api/v1/users` to show only requests whose path contains `/api/v1/users` )
+  - Modify the contents of intercepted packets before forwarding them to the destination
+  - Resend (or replay) captured packets with or without manually modifying the contents
   - Show differences between any two received packets
-- **Many protocols support**
-  - Support HTTP1, HTTP2, HTTPS, WebSocket, FireBase, MQTT, gRPC, Protocol Buffers, MessagePack and CBOR as built-in protocols.
-  - Develop new protocols easily
-- **Features for application penetration test**
-  - Send concurrently multiple packets for a DB transaction test
-  - Replace server certificate with self signed certificate for a client side validation test
-- **Other advantages**
-  - Have a built-in DNS server for easy packet forwarding
-  - Save/Load project data
+- **Support for protocols over TCP/UDP, not limited to HTTP/HTTPS**
+  - Built-in encoders/decoders enable users to inspect/intercept HTTP1, HTTP2, HTTPS, WebSocket, FireBase, MQTT, gRPC, Protocol Buffers, MessagePack, and CBOR messages
+  - Easy to develop an extension to decode/encode protocols not listed above
+- **Features for application penetration tests**
+  - Send multiple packets simultaneously to test race conditions or any inconsistent state due to improper synchronization/locking.
+  - Even possible to simultaneously send packets with different messages. ( `Bulk Sender` )
+  - Replace a server certificate with a self-signed one for testing if a client app properly validate certificates
+  - Embedded an easy to configure DNS server to route requests from a client to PacketProxy, which is one of the easiest ways to proxy packets transparently
+  - Save/Load settings and history data of a project as an SQLite3 file
   - Support Windows, macOS, and Linux
 
-# Setup
-  
-[Download](https://github.com/DeNA/PacketProxy/releases) the version corresponding to your OS and run the installer. 
+# Install
 
-Or
+The recommended way to install PacketProxy is to download installers for your platform from the PacketProxy's [release](https://github.com/DeNA/PacketProxy/releases) page and execute it.
 
-Just type `$ brew cask install packetproxy` if you use Homebrew-cask on MacOS.
+You may also use Homebrew-Cask to install PacketProxy if your platform is macOS. In that case, installation is done by just typing `$ brew cask install packetproxy`
 
-# Usage
+# Using PacketProxy
 
-Please see this page: [For Users](https://github.com/DeNA/PacketProxy/wiki/Using-PacketProxy)
+Take a look at this page to get started: [For Users](https://github.com/DeNA/PacketProxy/wiki/Using-PacketProxy)
  
-# Development
+# Extending PacketProxy
 
-If you want to develop support for additional protocols or improve on the base PacketProxy application, please refer to this page:
-[For Developers](https://github.com/DeNA/PacketProxy/wiki/Developing-PacketProxy)
+If you want to develop an extension to support additional protocols or improve core functionalities/UIs, please have a look at this page: [For Developers](https://github.com/DeNA/PacketProxy/wiki/Developing-PacketProxy)
 
  
 # License
 
-Apache License 2.0
+This program is distributed under Apache License 2.0