SGML (Standard Generalized Markup Language)

Standard Generalized Markup Language (SGML) is a system for defining rules for how documents can be structured and formatted, similar to a blueprint for building a house. It allows different types of information, like text and images, to be organized in a consistent way, making it easier to share and manage data across different platforms. While SGML itself is quite complex, it serves as the foundation for more user-friendly markup languages like HTML and XML, which are widely used for websites and data interchange.