If you ever find one of your files not working for some strange reason then maybe you may want to check the file extension. And it can also be a neat trick to play on one of your friends. Every file has its own internal file signature that says exactly what kind of file it is, however this signature is not displayed normally. What you normally see is an external file signature, which can easily be manipulated with the rename feature of an operating. If the external signature does not match the internal one, then when the file is selected to be run, it will not run correctly and you might receive an error. This rather simple trick, but largely overlooked aspect of why some files don’t work is why with a little knowledge about this you can either help your friends get that “Beethoven.jpg” to play in on their iPod’s correctly, since it should actually be called “Beethoven.mp3”.
This is actually what many people do when trying to cover up files that they have on their computers. Changing “Bank Robbery Plans.doc” to “My Summer Vacation.png” can distract one from what is actually there. This is just one way to take attention away from sensitive data that you may have one you computer. Want to use technology to mess with your not so tech-savvy friends even more, take their files and move them into a folder and set its properties to hidden and as like magic, they will not be able to see their files, unless there enable the show hidden files option, which is disabled by default.This is also a good way to prevent yourself from accidentally deleting important documents that you need.
*For informational purposes only
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