What is an API? Every Developer Should know This? | Explained in Hindi | System Design Foundation

API is one of the most used words in tech and one of the most poorly explained. Every developer interview touches it. Every system design round assumes you know it cold. In this video we explain exactly what an API is, how it works under the hood, and what the four components of every API call actually do — using examples that make it impossible to forget. What we cover: 🔹What API actually stands for and what it means in plain English 🔹The bridge and messenger analogy — how two software systems talk to each other 🔹Real world example — how your phone's weather app uses a Weather Service API without tracking anything itself 🔹How developers define URL-based operations to expose data to other systems 🔹The 4 components of every API call — Endpoint, HTTP Methods, Headers, and Payload 🔹GET, POST, PUT, DELETE — what each one does and when to use which 🔹Auth tokens in headers — how APIs verify identity 🔹JSON payload — what actually travels inside an API request 🔹Overview of REST, SOAP, and GraphQL — the three most popular API types in production today Exact Interview Answer: "An API — Application Programming Interface — is a defined contract that allows two software systems to communicate. One system sends a request to a specific endpoint using an HTTP method — GET to retrieve data, POST to create, PUT to update, DELETE to remove. Each request contains headers for metadata like authentication tokens and optionally a JSON payload carrying the actual data. The server processes the request and returns a structured response. REST, SOAP, and GraphQL are the three most widely used API architectural styles, each with different trade-offs in flexibility, strictness, and query efficiency." 💬 Drop your questions in the comments — I read everything. 💾 Save this. This comes up in every backend and system design interview. 🔔 Subscribe @SatyamScripts for the complete System Design Foundation Series every week. Tags: what is an API, API explained simply, API for beginners, REST API explained, HTTP methods explained, GET POST PUT DELETE, API endpoint explained, JSON payload API, API headers auth tokens, GraphQL vs REST vs SOAP, system design foundation, backend engineering basics, API system design interview, what is REST API, API call components, developer fundamentals 2026, tod phod system design, software engineering interview prep, API tutorial Hindi, system design for beginners