App Building & Devbeginner
API Key
Application Programming Interface Key
Definition
A unique code that lets one application access another's services. Like a password that software uses instead of a human. It proves your app has permission to use a service.
Why it matters
API keys are how you connect tools: your website to Stripe, your app to OpenAI, your store to a shipping provider. Keeping them secret is critical, a leaked key can rack up costs or expose data.
Example
A founder adds her OpenAI API key to her .env file so her app can generate AI responses. She stores it securely and never commits it to GitHub.
Related terms
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