APIs

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Types of APIs

1. REST API

• The most common API used today.

• Works over HTTP and uses methods like GET, POST, PUT, DELETE.

• It is stateless, meaning each request is independent.

Example:
When a mobile app requests user data from a server.

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2. SOAP API

• A strict and highly structured API protocol.

• Uses XML format.

• Known for high security and reliability.

Used in:

• Banks

• Healthcare systems

• Government systems.

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3. gRPC API

• Developed by Google.

• Uses Protocol Buffers instead of JSON.

• Very fast and efficient for microservices.

Used by:
Large-scale systems like Netflix and Uber.

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4. GraphQL API

• Created by Facebook.

• Allows clients to request exactly the data they need.

Advantage:
Avoids over-fetching or under-fetching data.

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5. Webhooks

• A reverse API.

• Instead of requesting data, the server automatically sends data when an event happens.

Example:
Payment gateway sending notification after payment success.

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6. WebSockets

• Enables continuous two-way communication between client and server.

Used for:

• Chat apps

• Live notifications

• Online gaming.

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7. WebRTC

• Used for real-time peer-to-peer communication.

Examples:

• Video calls

• Screen sharing

• Real-time collaboration tools.

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Key Takeaway

Different APIs are designed for different purposes:

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