What Is an API: The Restaurant Menu Analogy
~10 min read
An API is a defined way for two pieces of software to talk to each other — like a restaurant menu, it lists exactly what you can ask for and what you'll get back, without you needing to know how the kitchen works.
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Key points
- •An API is a defined way for two pieces of software to talk to each other, like a restaurant menu defines what you can order and what you'll get
- •Your code (the customer) sends a REQUEST; the API provider's system (the kitchen) does the internal work and sends back a RESPONSE
- •Abstraction means you only need to know the 'menu' (valid requests and response shapes) — not how the provider implements anything internally
- •This request/response pattern lets software built by different teams, in different languages, on different machines, work together seamlessly
- •Every LLM you access through code (GPT-4, Claude, Gemini) works exactly this way: you send a prompt as a request, get generated text back as a response