Some warnings are given at the end of the text. But, if you don’t read the whole text, you won’t understand some of that warning. So, read the full article.
Many people may not know what ‘data’ is. Data is any quantitative information or object that is numerical such as audio, video, picture, message etc. So when we delete these data from our mobile or computer, but really mobile or, they do not go away from the computer forever. Rather, the data stays on the memory card or hard disk.
Let’s explain with computer hard disk. Audio to computer, video is all a data consisting of binary numbers 1 and 0. So, your computer needs to know which is the picture, which is the audio, which is the video. For this, every data has a format. The computer can understand through the format – which is audio and which is video. Again, this audio, video etc. extension is used at the end of the file name such as: .jpg, .jpeg, .png, .bmp after the image name. Again, after the video name .mp4, .3gp, .webm etc. are written. These are called extensions. With this extension, your computer can understand – the file you are clicking on, you need to open it with any software. Because of this extension, if you open a PDF book, it does not bother to open with any audio player.
However, when you download an audio or video, the audio, video data is magnetically stored on the computer’s HDD hard disk via a file system called NTFS on your Windows computer. And, there is a database called computer registry, where a list of what is on your computer is registered.
Now if you delete any data but that data remains on the computer hard-disk. Simply, the name of the deleted data is deleted from this registry database. As well as the file that was deleted on your computer, the first letter of the name that was saved on the computer is deleted. As a result, two things happen-
1. After deleting, the first letter of the name of the deleted file is deleted and the file becomes unknown to the computer. This informs the computer that the unknown data is stored in the memory where the newly downloaded data is stored and the deleted data is allowed to be deleted permanently.
2. After deleting, the deleted file is deleted from the registry. As a result, the file disappears from your computer’s operating system even if it is on the computer.
For this reason, after deleting the deleted file remains on the computer, but they can not be seen. And, since it stays on the computer; So, where the deleted data was in memory, it is possible to download any new data and restore it before overwriting it.
Now the question that may come to the mind of many is: “When we delete data, if the computer had overwritten any other data in place of that data, then that data would have been deleted forever? As a result, no one else could see our deleted data! ”
Yes, that’s right. But, then it took a long time to delete a data; So, that is not done.
Also, there is another method called ‘0 filling’. As I said at the beginning of the article, the audio, video to the computer are all binary 0 and 1 numbers. And, suppose these numbers are on the magnetic hard disk as follows-
1 remains thus-.
0 stays like this- _
So, one thing can be done to permanently delete deleted data. And, that is – replacing all 1 binary numbers with 0. Suppose the structure of an audio is as follows-
_ _ | _ | | _ _ _ _ _ | _ _ | _ _ _ _
1 = |
0 = _
So, when you delete this audio, all 1 numbers are changed to 0 accordingly-
It was before
_ _ | _ | | _ _ _ _ _ | _ _ | _ _ _ _
After deleting will be:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
If you use this method, even though your deleted data will remain on the computer, its appearance will change completely. However, there is light talk about this method. And, that’s– when the number 1 is | When it is converted to _ then it is not completely straight like _ and becomes a bit dull. As a result, it is possible to retrieve deleted data and retrieve information from others. Because, you can easily see the curved marks – it was actually 1. But, it costs a lot of money to do this.
Be careful not to upload any personal photos on the Internet. You may be uploading pictures or videos privately. However, you must know that even if you delete these images, they will not be deleted from the server memory of the website you uploaded the image to. Be careful even when selling your mobile, computer. Fill the memory by deleting all the data from the memory card or hard disk a few times and downloading some unnecessary data.
Remember – knowledge and awareness is the key to security.
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