Text files contain text data that can be saved in either a plain text format or a rich text format. If you’re using Windows and create a Word document it is saved as a .DOCX file (rich text format). There are other ways to create text files. Sometimes you just make a not on Wordpad and when you save the document it becomes a .TXT file (plain text format).
Popular text file extensions are .TXT, .DOCX, .XML, and .SRT.