Website vs Web service

The basic difference of a website vs a web service is that:

Website/Web application: Returns a slew of web pages served by a web server (e.g. IIS) that are human readable via a browser. 

Web Service: Returns data in various formats (xml, json, etc), depending on the protocol (SOAP, HTTP,etc) that is machine understandable, usually for other applications to use that data. If you want to have that data human-readable then a web page that consumes that data, has to be built which is then rendered by the browser. 

Programmers - web service returns pure objects whereas web site renders data in web pages which can be rendered by the browser.