--- layout: "language" page_title: "Backend Overview - Configuration Language" description: "A backend defines where Terraform stores its state. Learn about how backends work." --- # Backends Backends define where Terraform's [state](/docs/language/state/index.html) snapshots are stored. A given Terraform configuration can either specify a backend, [integrate with Terraform Cloud](/docs/language/settings/terraform-cloud.html), or do neither and default to storing state locally. The rest of this page introduces the concept of backends; the other pages in this section document how to configure and use backends. - [Backend Configuration](/docs/language/settings/backends/configuration.html) documents the form of a `backend` block, which selects and configures a backend for a Terraform configuration. - This section also includes a page for each of Terraform's built-in backends, documenting its behavior and available settings. See the navigation sidebar for a complete list. ## What Backends Do Backends primarily determine where Terraform stores its [state](/docs/language/state/index.html). Terraform uses this persisted [state](/docs/language/state/index.html) data to keep track of the resources it manages. Since it needs the state in order to know which real-world infrastructure objects correspond to the resources in a configuration, everyone working with a given collection of infrastructure resources must be able to access the same state data. By default, Terraform implicitly uses a backend called [`local`](/docs/language/settings/backends/local.html) to store state as a local file on disk. Every other backend stores state in a remote service of some kind, which allows multiple people to access it. Accessing state in a remote service generally requires some kind of access credentials, since state data contains extremely sensitive information. Some backends act like plain "remote disks" for state files; others support _locking_ the state while operations are being performed, which helps prevent conflicts and inconsistencies. -> **Note:** In Terraform versions prior to 1.1.0, backends were also classified as being 'standard' or 'enhanced', where the latter term referred to the ability of the [remote backend](/docs/language/settings/backends/remote.html) to store state and perform Terraform operations. This classification has been removed, clarifying the primary purpose of backends. Refer to [Using Terraform Cloud](/docs/cli/cloud/index.html) for details about how to store state, execute remote operations, and use Terraform Cloud directly from Terraform. ## Available Backends Terraform includes a built-in selection of backends, which are listed in the navigation sidebar. This selection has changed over time, but does not change very often. The built-in backends are the only backends. You cannot load additional backends as plugins.