Which file extension is commonly used for web pages?

The file extension commonly used for web pages is .html. This stands for HyperText Markup Language, which is the standard language used to create and design documents on the World Wide Web. HTML files are structured in a way that web browsers can interpret and render them as web pages, allowing for the incorporation of text, images, links, and other multimedia elements.

The other file extensions do have their uses but serve different purposes. For example, .xml (eXtensible Markup Language) is used primarily for storing and transporting data rather than displaying it as a web page. It allows for the definition of custom markup, but it is not designed for direct presentation in browsers. The .txt extension refers to plain text files, which contain no formatting and are not suitable for creating structured web pages. Lastly, .docx is a Microsoft Word document format, primarily used for word processing tasks, and is not applicable for web page creation.

Therefore, .html is the appropriate and widely accepted format for web pages, making it the correct choice.