Stage 1 · Lesson 10 of 10
HTTP methods and status codes
The says what the client wants to do. GET reads, POST creates something or triggers an action, PUT replaces a thing, PATCH changes part of it and DELETE removes it. Two properties matter for everything later.
Safe methods (GET, HEAD) change nothing on the server. Idempotent methods (GET, PUT, DELETE) have the same effect whether they run once or five times. That decides what a client may safely retry after a timeout.
are three-digit answers grouped by their first digit: 2xx means success, 3xx a , 4xx the client's fault and 5xx the server's fault. Learn 200, 201, 204, 301, , 400, 401, 403, 404, 409, 422, , 500 and 503 by heart.
Common trapreturning 200 with an error message in the body, which misleads every client and monitor.
A question to check yourself, an AI practice session and 2 cheat sheet entries come with the full roadmap. Unlock
Resources for this stage
Start with· follow one of these
- CoursePaidGrokking Python Fundamentals
Design Gurus · Beginner · $50
Python basics in a sensible order: collections, functions, classes and modules
- CourseFreeCS50's Introduction to Programming with Python
Harvard University · Beginner
Free Harvard course with real problem sets, and it teaches unit tests early
Practise
Keep handy
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