Update README.md

README.md

@@ -16,7 +16,7 @@ Travis CI: [![Travis CI](https://travis-ci.org/shadowsocks/shadowsocks-libev.svg
 ## Features
 
 Shadowsocks-libev is written in pure C and depends on [libev](http://software.schmorp.de/pkg/libev.html). It's designed
-to be a very simple implementation of shadowsocks protocol, in order to keep the resource usage as low as possible.
+to be a lightweight implementation of shadowsocks protocol, in order to keep the resource usage as low as possible.
 
 For a full list of feature comparison between different versions of shadowsocks,
 refer to the [Wiki page](https://github.com/shadowsocks/shadowsocks/wiki/Feature-Comparison-across-Different-Versions).