Definitions

Flavor

Or Flavour if you're from anywhere but the USA. This defines a variety of details about the virtual hardware used for a VM:

Horizon

This is the web-based UI for OpenStack

HOT

Short for Heat Orchestration Template. This is a Domain Specific Language based on YAML which is used to define an OpenStack HEAT stack. OpenStack HEAT also supports amazon Cloudformation templates, but we'll be ignoring that for this introduction.

Output

When a HEAT template is deployed, the output is stored and can be reviewed later on, either via the stack-show command, or in the Horizon dashboard. This data is called the "Output".

Parameters

A HEAT template can include "Parameters" which allow for predefined and/or modifiable details about the infrastructure to deploy. For example, a parameter might be the ID of a VM Image to use for the HEAT template, allowing for VM images to be modified or updated, while still deploying the same overall architecture.

ResourceGroup

A group of resources. Used to group together, and multiply, a set of resources inside of a template.

Resources

Resources are the specific objects that Heat will create and/or modify as part of its operation. This can include infrastructure such as networks or virtual machines, but can also include other metadata such as randomly generated passwords.

Stack

A HEAT "stack" is the collection of objects or resources which will be created by a HEAT template when deployed. This might include virtual machines, nics/ports, networks, routers, security groups, keypairs, auto-scaling rules, etc.

Template

A template is a YAML based declarative DSL which defines the state of a deployed application stack.