Java internationalization is the process of designing and implementing software applications that can be adapted to different languages and cultural preferences. The goal of internationalization is to make software products that are usable and meaningful to users from different regions and cultures.

Java provides several APIs to support internationalization, including the java.util.Locale class, which allows you to identify a user's language and cultural preferences, and the java.text.NumberFormat and java.text.DateFormat classes, which enable you to format numbers and dates according to the user's locale.

When developing an internationalized Java application, you should follow some best practices, such as avoiding hard-coded strings and externalizing them in resource bundles. You should also ensure that the user interface is designed to handle the different text direction and layout preferences of different languages.

Java also provides support for right-to-left languages, such as Arabic and Hebrew, by enabling developers to use a mirrored version of the user interface for these languages.

In summary, Java internationalization is an essential aspect of software development that enables software products to be used by people from different regions and cultures. Java provides several APIs and best practices to support internationalization, and it is important to follow these guidelines when developing internationalized Java applications.