How does a markup language primarily differ from a programming language?

The primary distinction between a markup language and a programming language lies in their fundamental purposes and functions. Markup languages are designed to structure and format data, allowing for the presentation of content in a readable manner, often used in documents such as HTML or XML. Their main role is to describe the data and how it should be organized, rather than to implement logic or behavioral operations.

In contrast, programming languages are built to define behaviors, execute algorithms, and perform logic operations. They contain constructs that allow for decision-making, data manipulation, and flow control, which are not present in markup languages. This foundational difference highlights why the correct answer emphasizes the role of markup languages in structuring data rather than defining behaviors.

Moreover, markup languages do not require compilers in the way programming languages do; they are typically interpreted by browsers or other applications without needing a compilation step. Additionally, while markup languages do have syntax rules, they are generally more lenient compared to the strict syntactical requirements of programming languages.