docker-docs/compose/environment-variables/index.md

title, description, keywords

title	description	keywords
Overview	Explainer on the ways to set, use and manage environment variables in Compose	compose, orchestration, environment, env file

{% include compose-eol.md %}

Environment variables can help you define various configuration values. They also keep your app flexible and organized.

This section covers:

• The various ways you can set environment variables in Compose.
• How environment variable precedence works.
• The correct syntax for an environment file.
• Changing pre-defined environment variables.