Fundamentals
The first 10 minutes of learning APIs — protocol-agnostic basics.
What is an API? A Plain-English Guide for Testers
An API is how two pieces of software talk to each other. Here's what that actually means — with runnable examples.
HTTP Methods Explained: GET, POST, PUT, PATCH, DELETE, QUERY
GET, POST, PUT, PATCH, DELETE — the five verbs that carry 99% of API traffic — plus QUERY, the emerging method for safe reads with a body. Here's what each one means, with runnable examples.
HTTP Status Codes: The Complete Tester's Reference
2xx means success, 4xx means you messed up, 5xx means they messed up — but the details matter. Here's the list every tester should know by heart.
Request & Response Anatomy: Headers, Bodies, and Everything In Between
Every HTTP request has the same parts. Once you know them, every API you'll ever test becomes readable.
Query Parameters, Pagination, Sorting & Filtering
Every useful API returns lists of things. Here's how to page through, sort, and filter them — with runnable examples.
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