What is API ? API Stands for Application Programming Interface They enable systems to share & update information among each other. Since different applications are built on different technologies, APIs provide a standard set of rules and protocols to communicate with each other To use an API, you do not need to be concerned about the internal implementation as long as you follow these rules and protocols. Eg. It is like driving a car. What you need is to know is how to use the accelerator, brake, gear, steering wheels etc. and don’t really need to bother yourself with the mechanics of how the car engine works. Protocol: In simple terms a protocol defines a set of rules & standards used by two or more parties to communicate with each other. Protocols include definitions of message format, data types, data flows etc. The are two main protocols for Web Services REST API SOAP API Bulk API Streaming API Though there are other protocols also like RPC, Bauyex, WSFL, BEEP etc., Sal...