Which format is typically used for file saving in word processing applications?

The DOCX format is typically used for file saving in word processing applications because it is the default file format for Microsoft Word and many other word processors. This format allows for efficient storage of text documents while supporting complex features such as formatting, images, tables, and various types of embedded content. DOCX files are based on XML, making them more efficient and easier to recover if corrupted compared to older file formats.

In contrast, JPEG is a format primarily used for images, MP3 is a format for audio files, and HTML is used for web pages. Each of these formats serves distinct purposes unrelated to text document editing and formatting, making them unsuitable for word processing tasks.