Web is evolving very rapidly and so we have to. And demands of generic things are increasing as well.
We all know now days no application stands alone, because there are a lot of types of devices available
So we have to create services which can be called by any kind of device and business logic can be placed at a single place.
And when it comes to fetch data from a web service method, client devices don’t always need whole data, sometimes needs few columns or sometime needs data filtered on some basis and so on.