Application Programming Interface (API)

What is Application Programming Interface ?

Through an API, a program can ask another program for information or actions and get a response without having to understand the underlying workings of the other program.

In the example for Application Programming Interface, a restaurant waiter is the best example. The reason for saying this is that the waiter position is similar to API. The waiter receives an order from you, the customer. Your request is communicated to the chef (the server) by the waiter (the API). After processing the request and preparing the food, the chef hands it to the waiter. It is returned to your table by the waiter (answer).

In the same way, the API takes the request from the client and sends a request to the server and accordingly the response from the server is sent to the client by APL

Why do We need APIs ?

Building scalable, adaptable, and networked systems requires APIs. Developers depend on them for the following reasons:

• Reusability: Use pre-existing APIs (such as the Google Maps API and Stripe Payments API) to    avoid starting from scratch.
• Efficiency: Integrate pre-made features to reduce development time.
• Scalability: Make it possible for dispersed, modular systems to expand readily.
• Integration: Link various web, mobile, IoT, or analytics platforms.
• Automation: Without human input, machines can communicate with one another using APIs.

How do APIs work ?

A request-response cycle between a client and a server is how APIs function.

• Request: An API endpoint (URI) receives a request from the client.
• Processing: The request is sent to the server by the API.
• Reaction: The requested data is processed by the server and returned.
• Delivery: The client receives the server's answer via the API.

Types of API Architectures

• REST API – Uses standard HTTP methods to exchange data, usually in JSON format, in a simple and scalable way.
• SOAP API – A protocol-based API that uses XML and strict standards for secure and reliable communication.
• GraphQL API – Allows clients to request exactly the data they need through a single endpoint.
• RPC API – Enables a client to execute functions or procedures on a remote server as if they were local.
• WebSocket API – Provides full-duplex, real-time communication between client and server over a persistent connection.