File names, extensions, and URLs

Quoting data files and electronic documents

In general, only quote file names in text if the detail is warranted—for example, when instructing the reader to type a file name or when describing the files contained in a folder. If the file name is intended to be typed, follow the guidelines for formatting folder names.

Otherwise, describe the file in text and provide the details in a footnote, a bibliography, a table, or an appendix. Unless the file name is intended to be typed, do not ornament with italic or such.

Formatting folder names and drive names

For references to the Microsoft Windows system, use title caps for file names, folder names, and drive names. Use all upper case for extensions when on their own. For case-sensitive systems like Unix, use the exact spelling.

Folder and drive names

.COM file

C:\Data\Management.xls (Windows)

Format file names, folder addresses, and URLs that are intended to be typed in monospaced font, which distinguishes numerical characters from alphabetical characters (Lucida Console is recommended).

Apply standard rules of punctuation before and after the file name or URL. Surrounding punctuation takes the format of the surrounding text. In particular, if the file name or URL comes at the end of a sentence, do not omit the ending period. The character format of the file name or URL helps to identify the difference between the file name and the surrounding punctuation.

You can capitalize medial letters for readability in concatenated file names if they won't be confused with function names, as in “ProductionSept09”.

Syntax of file names and network addresses

• Use “file” and or the document type (a spreadsheet, for example) when referring to the stored item.

• Use “folder” when referring to a storage location on a network or disk (not “directory”).

• Use “path” when referring to the address of a folder on a network.

• Use “address” when referring to a location on the Internet.

• The compound phrases “file name” and “path name” are not closed.

File name extensions

When describing a file type, capitalize and precede the file name extension with a period. Use the article (a or an) that applies to the sound of the first letter of the extension, as though the period (or “dot”) is not pronounced, as in “an .XLS file” and “a .PPT file”.

Do not use the term “file extension”; use “file name extension” or “extension”. If possible, write around the term: “Word adds .DOCX to the file name if you don't specify the file format.” In general, however, avoid the use of any extension. Describe the type of program or file instead—an application, a text document, a spreadsheet, and such.

Punctuation after a file name or internet address

Do not omit sentence punctuation after a file name or internet address. To distinguish between the address and the sentence punctuation, as appropriate, you can:

• Enclose file names with double quotation marks.

• Change the font, if intended to be typed. Ensure that any trailing punctuation is formatted in the style of the surrounding text.

• Apply a hyperlink style. Ensure that a trailing period is not included in the hyperlink address.

• In a bibliographic reference, enclose the URL with angle brackets < >.

Internet addresses

Details can be found at www.mysite.com.

Literals and placeholders

When instructing users to type literal file names and paths, use lower case bold for literals. Use italic for placeholders.

Literals and placeholders

In the Command line box, type...

c:\msmail\msmail.mmf password