Update README.md

README.md

@@ -19,14 +19,17 @@ You can connect all physical and logical channels with communication capabilitie
 ### Basic structure
 ```
 * You <-> Proxy client (Python) <-> Parasitized proxy server (Optional, PHP/LAMP) <-> On the Web
-* You <-> Proxy client (Python) <-> Connector extension (Optional, Python) <-> On the Web
+* You <-> Proxy client (Python) <-> Connector extensions (Optional, Python) <-> On the Web
 ```
 
 For example, build a simple web debugging proxy on the shared servers.
 
 ### Stateful mode
 This project supports two modes of connection. The default is stateless. You can use the stateful mode to avoid being constrained by transfer capacity limits. See the [Stateful mode (github.com/gnh1201/caterpillar wiki)](https://github.com/gnh1201/caterpillar/wiki/Stateful-mode).
 
+### Connector extension
+This project supports the implementation of connector extension. Examples include using it for web archives (caching) and serial communication.
+
 ## (Optional) Before to use
 If you have a server that ***will be parasitized*** and you want to proxy it, you should upload the `index.php` file to a shared server. The index.php file is located in the `assets/php` directory within this repository.