An application programming interface key (API key) is a code generated by websites that allow users to access their application programming interface. API keys are used to track how the API is being used in order to prevent malicious use or abuse of the terms of service.

API keys can be based on the UUID system to ensure they will be unique to each user.^[1]

The API key often acts as both a unique identifier and a secret token for authentication, and will generally have certain access rights on the API associated with it.

References

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