Notepad saves a file in .txt format. By using Print to PDF and Save As options, you can save it as PDF and HTML in Windows 11/10.

Free Web service Zamzar can turn Publisher files into Word documents, PDFs, HTML pages, and loads of other formats.

Learn how to use JavaScript’s fs library module to create, read, write, and stream common file types in the JavaScript runtimes Node, Deno, and Bun.

CSVFileView is a free portable tool that lets you open CSV files and manage data without using Excel or Google Sheets on Windows 11/10.