Update README.md

README.md

@@ -1,2 +1,18 @@
 # Block-Explorer [![Build Status](https://travis-ci.org/X9Developers/block-explorer.svg?branch=master)](https://travis-ci.org/X9Developers/block-explorer) [![Codacy Badge](https://api.codacy.com/project/badge/Grade/96a6179dc4c645bd96f9473fa069250d)](https://www.codacy.com/app/AlexITC/block-explorer?utm_source=github.com&utm_medium=referral&utm_content=X9Developers/block-explorer&utm_campaign=Badge_Grade)
-XSN Block Explorer
+
+The XSN Block Explorer (https://xsnexplorer.io/) is composed by several sub projects:
+- [server](server)
+- [web-ui](web-ui)
+- [infra](infra)
+
+## server
+The server is a backend service that interacts with the `xsnd` (RPC server) to provide a RESTful API for retrieving information from the blockchain, it also maps the blockchain to a relational database to support several operations that otherwise would kill the application performance.
+
+## web-ui
+The web-ui is the frontend application that interacts with the `server` project to display the data in a browser.
+
+## infra
+The infra project contains all stuff related to the required infrastructure, like deployment steps and hopefully deployment scripts (TODO).
+
+# Contributing
+We are happy to accept contributions, please read the [CONTRIBUTING.md](CONTRIBUTING.md] file to see our rules.