At its core, Argo CD treats Git as the single source of truth for application definitions. You declare the desired state of your Kubernetes applications in Git (manifests, Helm charts, Kustomize overlays), and Argo CD continuously compares that desired state with what is actually running in the cluster. When drift is detected, it can alert you or automatically reconcile the cluster back to the Git-defined state.

Argo CD runs inside Kubernetes and provides:

- Declarative application management
- Automated or manual sync from Git to cluster
- Continuous drift detection and health assessment
- Rollbacks by reverting Git commits
- Fine-grained RBAC and multi-cluster support

It integrates natively with common Kubernetes configuration formats:

- Plain YAML
- Helm
- Kustomize
- Jsonnet

Operationally, Argo CD exposes both a web UI and CLI, making it easy to visualize application state, deployment history, diffs, and sync status. It is commonly used in platform engineering and SRE teams to standardize deployments, reduce configuration drift, and enforce auditability.

Argo CD is part of the Argo Project, which is hosted by the Cloud Native Computing Foundation (CNCF), and is widely adopted in production Kubernetes environments ranging from startups to large enterprises.