Differences between main language and system language in Windows?

Here are the main differences between the main language and the system language:

1. Main language

- Definition:

The main language (also called "primary language" or "user language") is the language the user sets for displaying content, applications, and web pages.

- Usage:

- It mainly concerns the language in which user interface elements such as menus, dialogs, notifications, and applications are presented.

- This language setting is mainly chosen by the user and can be changed at any time.

- It is also used when displaying content in apps and on web pages, provided they support the user's preferred language.

- Examples:

If a user sets German as the main language, menus and dialogs in most applications and the user interface are displayed in German.

2. System language

- Definition:

The system language (also called "system language" or "base operating system language") is the language selected when the operating system is installed and is used for deep system communication.

- Usage:

- It is the language in which system components, standard applications, and the Windows logon screen are displayed.

- The system language also affects the language in which error messages and system information are displayed.

- This language can only be changed by reinstalling the operating system or using special system tools.

- Examples:

If the system language is English, basic system messages, the logon screen, and standard tools such as Task Manager are displayed in English, even if the user's primary language is set to German.

Important differences:

- Flexibility:

The primary language can be flexibly changed by the user, while the system language can usually only be changed by reinstalling the system.

- Application:

The primary language mainly affects the user experience and presentation of content, while the system language affects basic system communication and messages.

- Location:

The primary language is set in the user settings, while the system language is often set during operating system installation or by special system tools.

Other relevant terms:

- Display or screen language:

This is often synonymous with primary language and refers to the language in which Windows interface elements are displayed.

- Input language:

This refers to the language and keyboard layout the user uses for input.

►►  Quickly change the Windows 11, 10, ... language with PowerShell   
►►  Windows 11 sometimes appears in different languages, why?

Summary

The primary language affects how content is displayed to the user and can be easily changed. The system language determines the deeper communication of the system and is less flexible as it affects basic system components.

This distinction is especially important for users who work in a multilingual environment or need to configure system settings for different regions.