There are three main types of Magento 2 mode that your store can run under: default, developer and production. The default mode is the mode set when you first download the Magento application. Magento does not recommend using this mode when either carrying out development work, or when running the application in a live environment.
You can change the mode to developer for example by running the following command provided by the magento file located in the bin directory.
Therefore if you cd into your Magento project’s root directory, you can run the following:
$ /path/to/your/php bin/magento deploy:mode:set developerIf you’re unsure what mode is currently set, you can run the following command to show you:
$ /path/to/your/php bin/magento deploy:mode:showWhat are the differences between the three modes?
You should use the developer mode when you are making customisations to the application. This is because using this mode will display error messages that will be visible on the browser rather than being logged to the log files.
In this mode, static view files are generated every time they are requested. They are written to the pub/static directory, but this has a negative impact on performance. However, this means that any changes made to the view files become immediately visible.
This mode should be used when deploying the website in a production environment. This mode is optimised for the highest performance.
In this mode, static view files are not created on the fly when they are requested; instead, they have to be deployed to the pub/static directory using the command-line tool when changes are made to the view files with the following command.
$ /path/to/your/php bin/magento setup:static-content:deployThe most important aspect of this mode is that errors are logged to the file system and are never displayed to the user. This is important for security reasons.
As the name implies, the default mode is used when no other mode has been specified within the application.
In this mode, errors are logged to files in the var/reports directory and are never shown to a user. Static view files are generated on the fly and then cached. This is different to using developer mode, as view file changes are not visible until the generated static view files are cleared.
Because the static files are created on the fly and then cached, it is not recommended to run a Magento store in a product environment in this mode because of the performance impact this has.
This mode is used when no other mode is specified, and so the mode should be changed to either developer or production after downloading the application, depending on what environment you run it on.
Note: This article is based on Magento CE version 2.1.