In real life, a file is kept in a folder (a file folder), and a folder can hold one or more files. If it holds only one, then the words are interchangeable; in computers, it is essentially the same, at least with my operating software, but the names are not interchangeable without modifying the software. I think.
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In real life if you have a filing cabinet I think a file contains multiple documents so it's the same as a folder so in real life they are the same thing but in a computer they are not. In a computer a file is a single document while a folder is just a container to hold multiple files or documents. Windows 95 is the first operating system to use the term Folder. Before that they were ca