What is Hyper Text Markup Language (HTML) primarily used for?

Hyper Text Markup Language (HTML) is primarily used for developing web pages. It serves as the foundational language used to structure content on the web. HTML provides a way to define various elements of a website, including headings, paragraphs, links, images, and other multimedia content. By using tags to format and organize this content, HTML enables browsers to render webpages in a visually appealing and accessible manner.

The other options do not align with the primary use of HTML. Building database management systems relates to different technologies such as SQL and databases, while creating executable files involves programming languages such as C++ or Python. Writing operating systems requires low-level programming languages and system architecture knowledge, rather than markup language capabilities. Therefore, the most accurate description of HTML's use is its role in developing web pages.