### [Install using the `apt` repository](https://docs.docker.com/engine/install/debian/#install-using-the-repository) Before you install Docker Engine for the first time on a new host machine, you need to set up the Docker `apt` repository. Afterward, you can install and update Docker from the repository. 1. Set up Docker's `apt` repository. ```bash # Add Docker's official GPG key: sudo apt update sudo apt install ca-certificates curl sudo install -m 0755 -d /etc/apt/keyrings sudo curl -fsSL https://download.docker.com/linux/debian/gpg -o /etc/apt/keyrings/docker.asc sudo chmod a+r /etc/apt/keyrings/docker.asc # Add the repository to Apt sources: sudo tee /etc/apt/sources.list.d/docker.sources <