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I know when a file is created date information such as date created, last modified, last opened, is automatically updated as meta data on that file. Is there other meta data though? Specifically, is there a way to tell what computer-name/user/whatever created a given file?

What is the extent meta data can be modified?

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    Unclear what help you need. Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it’s hard to tell what problem you are trying to solve or what aspect of your approach needs to be corrected or explained. See the How to Ask page for help clarifying this question.
    – gnat
    Oct 13, 2014 at 6:57
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    The meta data for a file is largely dependent on the file system, the operating system and the file type of the file. What OS are you using? On Linux you can see the owner of every file, though that won't necessarily be the creator as ownership can change. Oct 13, 2014 at 9:03

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Normally a file should not contain metadata. As the prefix meta indicates, metadata is beyond data. It belongs to a different realm where you are concerned with characteristics of the file to know what it is useful for, and that (usually) cannot be inferred with certainty or easily enough from the content. Putting that information in the file would interfere with the actual use of the file, as applications would have to know about it. Furthermore, you may want to allow different access regimes (use, modification) for the data and the metadata.

Such considerations show that metadata concerning the file is to be stored outside the file, though be associated with the file. Hence metadata is often managed in a different memory location, though associated with the file at OS level, either by the OS itself or by some applications.

From an implementation point of view, metadata could be stored in the file, if it is managed by the OS so that application receive a stripped file (without metadata) when they are not supposed to be metadata aware. This is also important when moving files to another OS.

This said, metadata can be any information about the data, that helps to better understand its relevance and usability for some purposes. It can be very general, such as date or location of creation, ownership, history, mutability, encoding standard, or very specific of some applications such as artistic school or style, library classification, keywords, etc.

In practice the kind of metadata available depends much on the operating system, or on the file system (especially on removable media). Some, such as access rights and date, may be found in the directory structure. Some can be inferred from the file name suffix, though this does not formally enforce its correctness. Some can be managed by the storage location, for example some directories may correspond to a specific role of files found in them. That is very variable. There are also special tools to retrieve metadata, when it is lost such as the file command in Unix.

Some files corresponding to a specific encoding scheme, such as JPEG, may contain in the file metadata that is meaningful for that encoding scheme. That is not a problem, since the existence of this metadata will be known to all applications accessing meaningfully the content of the file.

As you see, metadata can be any information about the file, whether technical or semantical. An it can be stored and associated with the file in a wide variety of ways. Also. what is metadata for one application may also be simply part of the file for other less knowledgeable applications.

What can be done with or to metadata is also very variable.

The origin of the file, such as computer-name or user-name is not standard on operating systems. But it does have owner, dates and access rights information, which may vary depending on operating systems and file systems.

The whole point of this is: to get a precise answer to your question, you have to make it much more specific, and make more precise whether you mean OS level, application level (which), encoding standard level, etc.

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