ICU
ICU (International Components for Unicode) is a mature, widely used C/C++ and Java library that provides robust and full-featured Unicode and globalization support for software applications. It includes components for text processing, locale-sensitive operations, character set conversion, and date/time formatting, enabling applications to work correctly across different languages and regions. The library is maintained by the Unicode Consortium and is used in many major operating systems, browsers, and applications to handle internationalization (i18n) and localization (l10n) tasks.
Developers should learn and use ICU when building applications that need to support multiple languages, scripts, or regions, such as global web services, mobile apps, or desktop software with international users. It is essential for tasks like proper text sorting (collation), character encoding conversion, date/time formatting, and handling complex text layouts (e.g., bidirectional text in Arabic or Hebrew). For example, a developer creating a multilingual e-commerce platform would use ICU to ensure product names are sorted correctly in different languages and dates are displayed in local formats.