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 API Protocols 


1. REST (Representational State Transfer)

- An architectural style for designing networked applications.

- It emphasizes stateless communication, the use of standard HTTP methods (GET, POST, PUT, DELETE), and resources identified by URLs.


2. GraphQL

- A query language for APIs that allows clients to request exactly the data they need, nothing more and nothing less.

- This efficiency is a major advantage over REST, where endpoints often return fixed data structures.


3. SOAP (Simple Object Access Protocol)

- A protocol for exchanging structured information in the form of XML messages over a network.


4. gRPC (Google Remote Procedure Call)

- A high-performance, open-source framework for remote procedure calls (RPCs).

- It uses Protocol Buffers (a compact binary format) for data serialization.


5. Webhooks

- A mechanism for real-time communication between applications.

- A webhook is essentially an HTTP callback triggered by a specific event in one system, which sends a notification to another system.


6. WebSockets

- A protocol providing full-duplex communication channels over a single TCP connection.

- WebSockets enable real-time data exchange between a client and a server.


7. MQTT (Message Queuing Telemetry Transport)

- A lightweight publish-subscribe messaging protocol designed for low-bandwidth, high-latency, or unreliable networks.

- It is commonly used in IoT (Internet of Things) applications.


8. AMQP (Advanced Message Queuing Protocol)

- An open standard protocol for message-oriented middleware.

- AMQP provides features like reliable message delivery, routing, and queuing, making it suitable for enterprise integration scenarios.


9. EDA (Event-Driven Architecture)

- A software architecture pattern where applications react to events (e.g., user actions, sensor readings).

- EDA promotes loose coupling and scalability.


10. EDI (Electronic Data Interchange)

- A set of standards for exchanging business documents (e.g., purchase orders, invoices) electronically between organizations.

- EDI is widely used in supply chain management and logistics.


11. SSE (Server-Sent Events)

- A server-push technology that allows a server to send updates to a client over an HTTP connection in a unidirectional manner.

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