Error while running application through NPM node and ember

I am new to this whole npm node concept and currently on learning phase. I am trying to resolve an error that is not letting me perform the Event router for my web application in node. Here is the error below and do let me know what is the problem or issue and what steps to take to resolve it.

Important: use process.env.PORT as the port and process.env.IP as the host in your scripts!

Debugger listening on port 15454
events.js:141
      throw er; // Unhandled 'error' event
      ^

Error: listen EADDRINUSE :::8080
    at Object.exports._errnoException (util.js:907:11)
    at exports._exceptionWithHostPort (util.js:930:20)
    at Server._listen2 (net.js:1250:14)
    at listen (net.js:1286:10)
    at Server.listen (net.js:1382:5)
    at EventEmitter.listen (/home/ubuntu/workspace/nodeproject/node_modules/express/lib/application.js:617:24)
    at Object.<anonymous> (/home/ubuntu/workspace/nodeproject/app.js:55:5)
    at Module._compile (module.js:409:26)
    at Object.Module._extensions..js (module.js:416:10)
    at Module.load (module.js:343:32)