What's the difference between web service and api

Question

can anyone tell me the difference between web service and web api

Amit Kumar Singh · Answer

API: An application programming interface (API) is a set of routines, data structures, object classes and/or protocols provided by libraries and/or operating system services in order to support the building of applications. Webservice: A Web Service is defined by the W3C as "a software system designed to support interoperable machine-to-machine interaction over a network" Clearly, both are means of communications. The diference is that Web Service almost always involves communication over network and HTTP is the most commonly used protocol. Web service also uses SOAP, REST, and XML-RPC as a means of communication. While an API can use any means of communication e.g. DLL files in C/C++, Jar files/ RMI in java, Interrupts in Linux kernel API etc. So, you can say that- 1. Web Service is an API wrapped in HTTP. 2. All Web Services are API but APIs are not Web Services. 3. Web Service might not perform all the operations that an API would perform. 4. A Web Service needs a network while an API doesn't need a network for its operation. ----------------------------------------------------------------------------------------------------------------------- An API (Application Programming Interface) is the means by which third parties can write code that interfaces with other code. A Web Service is a type of API, one that almost always operates over HTTP (though some, like SOAP, can use alternate transports, like SMTP). The official W3C definition mentions that Web Services don't necessarily use HTTP, but this is almost always the case and is usually assumed unless mentioned otherwise. For examples of web services specifically, see SOAP, REST, and XML-RPC. For an example of another type of API, one written in C for use on a local machine, see the Linux Kernel API. As far as the protocol goes, a Web service API almost always uses HTTP (hence the Web part), and definitely involves communication over a network. APIs in general can use any means of communication they wish. The Linux kernel API, for example, uses Interrupts to invoke the system calls that comprise its API for calls from user space.

Rajeesh Menoth · Answer

Hi, Web API is a newer Microsoft framework which helps you to build REST based interfaces. The response can be either JSON or XML A web service typically offers a WSDL from which you can create client stubs automatically Web Services are based on the SOAP protocol. Check the following reference : http://www.c-sharpcorner.com/blogs/difference-between-api-and-web-service1 http://stackoverflow.com/questions/19336347/what-is-the-difference-between-a-web-api-and-a-web-service