XML

XML (Extensible Markup Language) is a general-purpose specification for creating custom markup languages. It is classified as an extensible language because it allows its users to define their own elements. Its primary purpose is to help information systems share structured data, particularly via the Internet, and it is used both to encode documents and to serialize data. In the latter context, it is comparable with other text-based serialization languages such as JSON and YAML.
Projects: ExaroWriter, AdsPatcher, The Book of Life, Data Visualizator, GamblingCompliance.