Why a web service?

Now, we know what a web service is. So before proceeding to REST, it is important to know the need for a web service. Where can a web service be used?

As just defined, a web service is a system to support machine-to-machine inter-operable communication over a network. It is very useful for communication between different systems or devices. In our case, we will be using web services to provide an interface by which either a mobile application or a web application will be able to communicate with a server to get and store data. This will make the client-side application separate from the server side logic. And nowadays, SPAs (Single Page Applications) and mobile applications need to be stand alone, separate from server side and only interacting with server side logic with web services. So definitely web services are very much important nowadays. However, web service usage is not limited to client side application usage but it is also useful in server to server communication where one server acts as a client.