version Define the version used by docker-compose
service Each element that runs the application The web and db are defined as one element that runs an application
depends_on Determine container creation order and dependencies
tty: true Keep launching the docker-compose up container.
environment Add environment variables
volumes Specify the path of the configuration file to mount [An attempt to explain the meaning of "passing through the PATH" as clearly as possible](https://qiita.com/sta/items/63e1048025d1830d12fd #)
[I explained how to write docker-compose.yml](https://qiita.com/yuta-ushijima/items/d3d98177e1b28f736f04#version%E3%81%A3%E3%81%A6 #)