When you delete a file on your computer, where does it go? Most of us know that it goes to a digital “recycling bin”. The name of your recycling bin can vary depending on your operating system (Windows, macOS, or Linux) however they all work very similarly. When something is sent to the trash directory the icon will usually change, symbolizing that it contains recoverable files. Assuming you empty your trash directory, the files in the trash directory gets deleted.
After a file gets deleted the reference for that file is removed. In short, the computer can no longer see the file and the space reserved for that file can be replaced. The file may no longer be readable by the computer, but the file is still technically on the hard drive. It will remain on the hard drive until another file is saved on to the same location. This is how files can be recovered.
Assuming the file space hasn’t been replaced, data recovery software can be used to recover deleted files. Data recovery software and services are designed to rebuild the file reference and allow the computer to access the deleted file again. As stated above, this only works if the existing file address wasn’t over written with new data.
The question you may ask yourself is: “Why don’t computers just ‘delete’ the file?”. The answer is: deleting a file reference is a lot quicker than completely erasing a file by over writing it’s previous address with data. In short, this method is faster than erasing files.
High priority individuals or VIPs keep their deleted information secure by ensuring that the partitioned space for the deleted file is nullified. Essentially, they replace the old file location with random data which makes it extremely difficult for hackers to access deleted information.
TL;DR: When you delete a file it goes to your “recycling bin” or trash directory. When a file goes to the recycling bin it can be recovered, however if you “empty” your recycling bin the file gets deleted. When a file is deleted the reference for the file is removed and this allows the computer to overwrite the existing space with new data.
Because the reference for the file is removed and not the entire file, it is still accessible from the hard drive assuming that its file location isn’t over written with new data. Once the file location is over written with new data it makes it nearly impossible to recover it.
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