Internationalization (I18N) is the process of making software portable to other locales. To internationalize the application, you provide language-specific resources for any displayed text elements.
An international application must not contain any language-specific text elements in its source code. For maintenance reasons, SAP strongly recommends not to enter UI text elements directly in the coding.
The following text elements are displayed on the screen and therefore are candidates for translation:
● UI element texts
● Message texts
● View titles
● Window titles
● Simple type names
The Developer Studio provides tool support for making Web Dynpro applications available in several languages.
The default locale of an application can be defined as an application’s property. You can use a specific search process to determine the session locale used by the Web Dynpro runtime environment when starting an application.
...
1. To create a multilingual application, use the UI text tools provided by the Developer Studio. Do not enter UI text elements directly in the coding.
The system automatically creates S2X files that contain all information required for a correct translation.
2. Create the language-specific versions and translate the text elements.
More information: Translating UI Texts