Types of APIs in Coding / Software Development

Question

Anubhav Kumar · Answer

There are 5 main types of APIs:
REST APISOAP APIGraphQL APIgRPC APIWebSocket API
(Plus internal/private APIs, public APIs, partner APIs, etc.)
1. REST API (Representational State Transfer)
REST is the most commonly used API type on the web. It uses standard HTTP methods to allow communication between a client and a server.
Key Points
Uses 
HTTP methods: GET, POST, PUT, DELETEData format: JSON (mostly), XMLStateless communication
Use Case
Web applicationsMobile appsPublic APIs
Example
GET /api/users
2. SOAP API (Simple Object Access Protocol)
SOAP is a protocol-based API with strict standards and strong security features. It uses XML for communication.
Key Points
Uses XML onlyHighly structured and strictBuilt-in security (WS-Security)
Use Case
Banking systemsEnterprise applicationsLegacy systems
Example
andlt;soap:Envelopeandgt;
  andlt;soap:Bodyandgt;
    andlt;GetUserDetails/andgt;
  andlt;/soap:Bodyandgt;
andlt;/soap:Envelopeandgt;
3. GraphQL API
GraphQL allows clients to request only the data they need, reducing over-fetching and under-fetching of data.
Key Points
Single endpointClient controls data shapeStrongly typed schema
Use Case
Complex UI applicationsMobile apps with limited bandwidthMicroservices aggregation
Example
{
  user {
    name
    email
  }
}
4. gRPC API
gRPC is a high-performance API framework developed by 
Google. It uses Protocol Buffers and HTTP/2.
Key Points
Binary data (smaller, faster)Strongly typed contractsSupports streaming
Use Case
Microservices communicationReal-time systemsHigh-performance backend services
Example
service UserService {
  rpc GetUser (UserRequest) returns (UserResponse);
}
5. WebSocket API
WebSocket provides real-time, two-way communication between client and server over a single persistent connection.
Key Points
Full-duplex communicationNo repeated HTTP requestsLow latency
Use Case
Chat applicationsLive notificationsReal-time dashboards
Example
const socket = new WebSocket("wss://example.com/chat");
Summary Table
API Type
Best For
Data Format
REST
Web and Mobile apps
JSON
SOAP
Enterprise systems
XML
GraphQL
Flexible data fetching
JSON
gRPC
High-performance services
Protobuf
WebSocket
Real-time communication
JSON / Binary
and

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Types of APIs in Coding / Software Development

Anubhav Kumar

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1 Answers

1. REST API (Representational State Transfer)

2. SOAP API (Simple Object Access Protocol)

3. GraphQL API

4. gRPC API

5. WebSocket API

Summary Table

Liked By

API Type	Best For	Data Format
REST	Web & Mobile apps	JSON
SOAP	Enterprise systems	XML
GraphQL	Flexible data fetching	JSON
gRPC	High-performance services	Protobuf
WebSocket	Real-time communication	JSON / Binary