Let’s understand the below requirement
We have a weather forecasting application developed by the Company X,and this application has been developed in Java.
It will collect real time data of weather and display in the application front-end.
There is an existing application which gives real time weather data and this application has been developed in .NET
Now instead of developing our own application which can get the real time weather data, we can reuse the existing application.
But there is one problem here, our application is in Java and the application which we want to reuse is in .NET
Both are developed in different technologies.
How can we reuse .NET application in Java application ?
Solution is Web service, yes, web service comes in handy here as it enables us to communicate between different applications
Which are developed either in same technologies or in different technologies.
What is Web service ?
Web service can be defined as a Method of communication between 2 applications(without any concern of the technologies these applications are using)
either running on same or different platform over a network using a set of standards and protocols.
As you can see in the above diagram,
Java based application can communicate with .NET application,Mainframe application and also Java Application.
Similarly Mainframe and .NET applications can communicate with all other applications.
So web service can make us to communicate with application developed in any technology.
Two parties are involved in a Web Service
1. The party providing the service called as web service provider
2. The party using its service called as web service consumer.