terraform/website/source/docs/enterprise/glossary/index.html.md

---
layout: "docs"
page_title: "Terraform Enterprise Glossary"
sidebar_current: "docs-enterprise"
description: |-
  Terminology for Terraform Enterprise.
---

# Glossary

Terraform Enterprise, and this documentation, covers a large set of terminology adopted
from tools, industry standards and the community. This glossary
seeks to define as many of those terms as possible to help increase
understanding in interfacing with the platform and reading documentation.

### Authentication Tokens

Authentication tokens are tokens used to authenticate with Terraform Enterprise via
APIs or through tools. Authentication tokens can be revoked, expired
or created under any user.

### ACL

ACL is an acronym for access control list. This defines access
to a set of resources. Access to an object in Terraform Enterprise limited to "read"
for certain users is an example of an ACL.

### Alert

An alert represents a health check status change on a Consul node that
is sent to Terraform Enterprise, and then recorded and distributed to various
notification methods.

### Application

An application is a set of code that represents an application that should
be deployed. Applications can be linked to builds to be made
available in the Packer environment.

### Apply

An apply is the second step of the two steps required for
Terraform to make changes to infrastructure. The apply is the process
of communicating with external APIs to make the changes.

### Artifact

An artifact is an abstract representation of something you wish to
store and use again that has undergone configuration, compilation or
some other build process. An artifact is typically
an image created by Packer that is then deployed by Terraform, or used
locally with Vagrant.

### Box

Boxes are a Vagrant specific package format. Vagrant can install
and uses images in box format.

### Build

Builds are resources that represent Packer configurations. A build
is a generic name, sometimes called a "Build Configuration" when
defined in the Terraform Enterprise UI.

### Build Configuration

A build configuration are settings associated with a resource that
creates artifacts via builds. A build configuration is the name
in `packer push -name acemeinc/web`.

### Catalog

The box catalog is a publicly available index of Vagrant Boxes
that can be downloaded from Terraform Enterprise and used for development.

### Consul

[Consul](https://consul.io) is a HashiCorp tool for service discovery, configuration,
and orchestration. Consul enables rapid deployment, configuration, monitoring and
maintenance of service-oriented architectures.

### Datacenter

A datacenter represents a group of nodes in the same network or
datacenter within Consul.

### Environment

Environments show the real-time status of your infrastructure,
any pending changes, and its change history. Environments can be configured
to use any or all of these three components.

Environments are the namespace of your Terraform Enterprise managed infrastructure.
As an example, if you to have a production environment
for a company named Acme Inc., your environment
may be named `%{DEFAULT_USERNAME}/production`.

To read more about features provided under environments,
read the [Terraform](/docs/enterprise) sections.

### Environment Variables

Environment variables injected into the environment of Packer builds or
Terraform Runs (plans and applies).

### Flapping

Flapping is something entering and leaving a healthy state rapidly. It is typically associated with a health checks that
briefly report unhealthy status before recovering.

### Health Check

Health checks trigger alerts by changing status on a Consul node. That status
change is seen by Terraform Enterprise, when connected, and an associated alert is
recorded and sent to any configured notification methods, like
email.

### Infrastructure

An infrastructure is a stateful representation of a set of Consul
datacenters.

### Managed Node

Managed node is the billing metric for Terraform Enterprise. For Consul Enterprise, a node is a host
with a Consul agent on it. For Terraform Enterprise, a node is a compute
resource managed by Terraform. See [Managed Nodes](/docs/enterprise/billing)
for more details about which Terraform resources and resource properties are counted
as compute resources.

All [Terraform Enterprise features](/docs/enterprise) are paid.

### Operator

An operator is a person who is making changes to infrastructure or
settings.

### Packer

[Packer](https://packer.io) is a tool for creating images for platforms such as Amazon AWS,
OpenStack, VMware, VirtualBox, Docker, and more — all from a single
source configuration.

### Packer Template

A Packer template is a JSON file that configure the various components
of Packer in order to create one or more machine images.

### Plan

A plan is the second step of the two steps required for
Terraform to make changes to infrastructure. The plan is the process
of determining what changes will be made to.

### Providers

Providers are often referenced when discussing Packer
or Terraform. Terraform providers manage resources in Terraform.
[Read more](https://terraform.io/docs/providers/index.html).

### Post-Processors

The post-processor section within a Packer template configures
any post-processing that will be done to images built by the builders.
Examples of post-processing would be compressing files, uploading
artifacts, etc..

### Registry

Often referred to as the "Artifact Registry", the registry
stores artifacts, be it images or IDs for cloud provider images.

### Run

A run epresents a two step Terraform plan and a subsequent apply.

### Service

A service in Consul represents an application or service, which
could be active on any number of nodes.

### Share

Shares are let you instantly share public access to your running
Vagrant environment (virtual machine).

### State

Terraform state is the state of your managed infrastructure from the last
time Terraform was run. By default this state is stored in a local file
named `terraform.tfstate`, but it can also be stored in Terraform Enterprise
and is then called "Remote state".

### Terraform

[Terraform](https://terraform.io) is a tool for safely and
efficiently changing infrastructure across providers.

### Terraform Configuration

Terraform configuration is the configuration files and any
files that may be used in provisioners like `remote-exec`.

### Terraform Variables

Variables in Terraform, uploaded with `terraform push` or
set in the UI. These differ from environment variables
as they are a first class Terraform variable used in interpolation.