What command is used to build an image from a Dockerfile?

The command used to build an image from a Dockerfile is "docker build." This command processes the instructions specified in the Dockerfile, which define how the image is constructed. During the execution of "docker build," Docker reads the Dockerfile, executes the commands within it, and produces an image that can later be run to create containers.

The "docker build" command allows users to specify various flags, such as the context for the build (the location of the Dockerfile and associated files) and tags for naming the resulting image. This process is crucial in the Docker ecosystem because it allows developers to automate the creation of images for their applications, ensuring consistency and repeatability across different environments.

The other options do not relate to the image-building process. "docker create" is used to create a new container from an image, "docker compose" is a tool for defining and running multi-container Docker applications, and "docker install" isn’t a standard Docker command. Thus, "docker build" is the appropriate choice for building an image from a Dockerfile.