A Kubernetes Secret stores sensitive configuration data.
Secrets are commonly used for passwords, API tokens, TLS certificates, and private keys.
Important caution
Kubernetes Secrets are not automatically a complete secrets-management system.
They are stored separately from ordinary configuration, but the actual security depends on cluster configuration, RBAC, encryption at rest, and how applications consume them.
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Use a Kubernetes ConfigMap for non-sensitive configuration.
Use a Secret for values that should not be exposed as ordinary text.