Postman is an API platform that enables developers to design, test, document, monitor, and collaborate on APIs throughout their lifecycle. It provides a desktop application and web interface supporting HTTP, REST, GraphQL, WebSocket, gRPC, MQTT, SSE, MCP, and SOAP protocols. The 2026 v12 release made Postman AI-native and Git-native: collections are stored as YAML in your Git repository, Agent Mode handles tasks in natural language, and a new API Catalog gives teams a centralized view of every service in their organization. Postman centralizes the full API lifecycle—from design and mocking through testing, monitoring, and collaboration—making it an essential platform for API-first development teams.
What This Cheat Sheet Covers
This topic spans 34 focused tables and 252 indexed concepts. Below is a complete table-by-table outline of this topic, spanning foundational concepts through advanced details.
Table 1: HTTP Request Types
Every API call starts with choosing a verb, and the verb carries meaning beyond just "fetch" or "send." These are the methods you'll select in Postman's request bar — the everyday GET/POST/PUT/PATCH/DELETE plus the lesser-used HEAD, OPTIONS, and TRACE — and the key thing to internalize is which ones are idempotent and safe, since that's what determines whether a retry is harmless or destructive.
| Method | Example | Description |
|---|---|---|
GET https://api.example.com/users | • Retrieve data from a server • idempotent and safe — does not modify resources. | |
POST https://api.example.com/usersBody: {"name": "Alice"} | • Create new resources on the server • non-idempotent, typically includes a request body. | |
PUT https://api.example.com/users/123Body: {"name": "Bob", "age": 30} | • Replace an entire resource completely • idempotent — requires full resource representation. | |
PATCH https://api.example.com/users/123Body: {"age": 31} | Partial update — modifies only the provided fields of a resource. |