| review | `review/*` | `review.example.com` | `review/*` | The review cluster which runs all [Review Apps](../../ci/review_apps/index.md). `*` is a wildcard, used by every environment name starting with `review/`. |
| review | `review/*` | `review.example.com` | `review/*` | The review cluster which runs all [Review Apps](../../ci/review_apps/index.md). `*` is a wildcard, used by every environment name starting with `review/`. |
| staging | `staging` | `staging.example.com` | `staging` | (Optional) The staging cluster which runs the deployments of the staging environments. You must [enable it first](customize.md#deploy-policy-for-staging-and-production-environments). |
| staging | `staging` | `staging.example.com` | `staging` | Optional. The staging cluster that runs the deployments of the staging environments. You must [enable it first](customize.md#deploy-policy-for-staging-and-production-environments). |
| production | `production` | `example.com` | `production` | The production cluster which runs the production environment deployments. You can use [incremental rollouts](customize.md#incremental-rollout-to-production). |
| production | `production` | `example.com` | `production` | The production cluster which runs the production environment deployments. You can use [incremental rollouts](customize.md#incremental-rollout-to-production). |