What is the purpose of the command with the --dev flag during the development or build process of a project?

The --dev flag during development or build process of a project is usually used to install dependencies or run tools that are only needed in the development environment, but not in production.

For example, in PHP projects using Composer, the command:

composer install --dev

installs all dependencies, including those specified in the require-dev section (such as testing, debugging, documentation generation tools).

This allows developers to have a full set of development tools without increasing the size and complexity of the production build.

In other tools or build systems, --dev may include additional options, such as more detailed logging, running a server with hot-reload, etc.