Save files with different file extensions in Notepad

To save a document with an extension other than the one a program wants to use, enclose the entire name in quotation marks. For example, if you run Notepad and save a file under the name file1.dba, it will actually be saved under the name file1.dba.txt.
But if you type "file1.dba" (with quotes) then the document will be saved under the name file1.dba. Note that a document so-named cannot be opened via double-clicking since the extension is no longer ".txt"