Lesson 1496 of 1570
AI and What an API Actually Is (And Why It Matters)
Every AI app you've ever used talks to the model through an API — knowing what that means lets you build your own.
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What this lesson covers
Learning path
The main moves in order
- 1The big idea
- 2API
- 3integration
- 4building
Concept cluster
Terms to connect while reading
Section 1
The big idea
An API (Application Programming Interface) is the way one program talks to another. ChatGPT-the-app talks to GPT-4-the-model through an API. That same API is open to you — for cents per request, you can build your own homework helper, story generator, or chat character. The barrier to building your own AI app is lower than ever.
Some examples
- OpenAI API: 1M tokens of GPT-4o for ~$2.50.
- Anthropic, Google, Mistral all sell similar API access.
- No coding required for tools like Make.com, n8n, Zapier.
- Free tiers exist for learning.
Try it!
Visit platform.openai.com. Look at the API pricing page. Just seeing the numbers — that's already an unlock for what's possible.
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