What is the purpose of the <meta> tag in an HTML document?

The tag in an HTML document serves the important function of specifying metadata about the HTML document. Metadata is data that provides information about other data, and in the context of web pages, it can include various types of information such as the character set used, the author of the document, keywords for search engines, viewport settings for responsive design, and much more.

Using the tag allows developers to provide this information in a way that can be utilized by browsers and search engines, influencing how the page is displayed or indexed. For example, specifying the character set with <meta charset="UTF-8"> can ensure that the text on the page is rendered correctly across different devices and browsers.

Other options focus on different functionalities that are not related to the purpose of the tag. The linking of JavaScript files, layout definition, and image inclusion are handled by other HTML tags and attributes specifically designed for those tasks. This distinction makes the choice of the tag clear and essential in the structure of an HTML document.