​  For example, when you save a document in Word, the file now uses the .docx file name extension by default, instead of the .doc file name extension. Examples of domain names and explanation of whether they need to be registered or recorded at Cornell. There will be no way to distinguish it from all the other resumes with the same file name. © 2015 by the Board of Trustees of Northern Michigan University. The new image will then appear wherever the old one was used—in this case, an … See Showing File Extensions. All file systems follow the same general naming conventions for an individual file: a base file name and an optional extension, separated by a period. To find and report all C language source code files starting at the current directory, enter: find . Tip: Always add the