Thanks !

This is not a misspelling both docker-compose and docker compose exist:

The docker compose (with a space) is a newer project to migrate compose to Go with the rest of the docker project. This is the v2 branch of the docker/compose repo. It's been first introduced to Docker Desktop users, so docker users on Linux didn't see the command. In addition to migrating to Go, it uses the compose-spec, and part of the rewrite may result in behavior differences.

The original python project, called docker-compose, aka v1 of docker/compose repo, has now been deprecated and development has moved over to v2. To install the v2 docker compose as a CLI plugin on Linux, supported distribution can now install the docker-compose-plugin package. E.g. on debian, I run apt-get install docker-compose-plugin.