Advantages of Web Services

Reuse already developed(old) functionality into new software:

Lets understand with very simple example.Lets say you are developing a finance software for a company on java and you have old .net software which manages salary of employees.So rather then developing new software for employee part,you can use old software and for other parts like infrastructure you can develop your own functionalities.

Usability :

Web Services allow the business logic of many different systems to be exposed over the Web. This gives your applications the freedom to chose the Web Services that they need. Instead of re-inventing the wheel for each client, you need only include additional application-specific business logic on the client-side. This allows you to develop services and/or client-side code using the languages and tools that you want.

Interoperability :

This is the most important benefit of Web Services. Web Services typically work outside of private networks, offering developers a non-proprietary route to their solutions.Web Services also let developers use their preferred programming languages. In addition, thanks to the use of standards-based communications methods, Web Services are virtually platform-independent.

Loosely Coupled:

Each service exists independently of the other services that make up the application. Individual pieces of the application to be modified without impacting unrelated areas.

Ease of Integration:

Data is isolated between applications creating ’silos’. Web Services act as glue between these and enable easier communications within and across organisations.

Deployability :

Web Services are deployed over standard Internet technologies. This makes it possible to deploy Web Services even over the fire wall to servers running on the Internet on the other side of the globe. Also thanks to the use of proven community standards, underlying security (such as SSL) is already built-in.