Webservices (Guru99.com)

What is a Webservice?

• A web service is a software module that is designed to perform a certain set of tasks.
• It can be searched over the network (on the server where it it hosted) and invoked accordingly. 

• The requests to the server are made thru REMOTE PROCEDURE CALLS (RPC).
• The main component of a web service is the data which is transferred between the client and server and is in XML format. 
• So when applications talk to each other, they do in XML. 
• Webservice uses a SOAP protocol for sending XML data in between the applications. 
• Data is sent over in HTTP. 

Why do you need a Webservice?

• Web services provide a common platform that allows multiple applications built on various programming languages (Java, .NET, Angular JS, Node.js, etc.) to have the ability to communicate with each other. (Don't have to bother in what language the front-end is written.)

Types of web services

• SOAP web services
• 
  
• RESTful web services

 

API and Web Services (Udemy)

[Mulesoft]

API is the acronym for Application Programming Interface, which is a software intermediary that allows two applications to talk to each other. Each time you use an app like Facebook, send an instant message or check the weather on your phone, you’re using an API. 

Example - Online travel service that interacts with several other websites to collect data...

• API also provides a layer of security. Your phone's data is never fully exposed to the server, and likewise, the server is never fully exposed to your phone. Each communicates in small packets with only what is necessary - like ordering a takeaway.