This is quite debate-able topic, I think.

In my opinion when you have a defined style for

- text and heading fonts

- headers and footers

- margin and hyphenation

- paragraphs, sections and chapters

- etc.

and it is applicable and applied to the whole document, then the document is formatted, otherwise it is not.

For a text file, if it is following a defined style (that may be a subset of the document style) it is formatted.

@ Dear Abdul Malik Khan ,

Can you give me an example for unformatted files?

Do these files contain special characters?

Its easier to give an example of formatted file than to the unformatted file, but let me try to explain;

Unformatted file is the one that is not following any rule or the rule is unknown. So copying some text from a webpage might be an example; as the webpage follows some rule that was known to its creator, but for a user its unformatted as (s)he don't know the rule.

Now because of the unformatted nature, the file is difficult to handle by an automated (or manual) system.

Unformatted or formatted; both type of files can have special characters.

Dear Abdul Malik Khan

You explained very well, I understood it. Thank you.