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API

Application Programming Interface

Definition

A set of rules that lets different software applications talk to each other and share data. APIs are how apps integrate with other tools.

Why it matters

Understanding APIs, even at a surface level, helps you build more powerful automated systems. Most no-code tools use APIs under the hood.

Example

Your Shopify store uses the Klaviyo API to automatically add every customer to your email list. Your Zapier automation uses the API to send a welcome email. All invisible, all API-powered.

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