I don’t understand the help document about localizing gear widget- Where and How is LANG_JSON_DATA defined?

I have not coded javascript for a while .. the help document says

“Define a global JS object in the resource file. In the following example, the JS object is LANG_JSON_DATA. This object defines the key-value pairs for localized strings”

then make folder for each locale and create langugae.js file (JSON data) and the runtime will load the correct locale!!