A markup language is used to annotate text, which indicates how the text should be structured, laid out, or styled. HTML is an example of a markup language that structures and styles content on the web. Unlike programming languages that contain instructions for computations, markup languages are designed to define the presentation of the text. Scripting languages, on the other hand, are typically used for automating tasks within a system or application, and high-level languages are used for general-purpose programming.