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How Permadelete works
When a file is deleted, only a reference to the location of the file is deleted. In other words, the file system just "forgets" that the file exists. But the actually data, the 0's and 1's, still remain on the disk. They will eventually be replaced by other files and data, but this can take a long long time. But file shredding apps like Permadelete make sure the files you delete can't be recovered.
They overwrite the actual data with dummy and useless data. While some file shredding apps use from three up to thirty five passes, Permadelete only overwrite the files once. Why? Because it's not necessary. Overwriting the file with random data once is enough to ensure that the file cannot be recovered. Plus, Multiple passes can be very time consuming and it can also, in some cases, damage the drive.
SSDs are newer than HDDs and they have some of their own unique properties. One of them is that they are NAND based memories. Which means that new data never replaces old data, which makes the old method of shredding files useless. But to make up for that they have a process called Garbage Collection in which data that are no longer needed are removed from the disk to free up memory. And most modern ones have another feature called TRIM. Which basically lets the Operating system notify the disk when a file is removed and marks the data useless. These two features together result in a phenomenon called Data Evaporation. Data Evaporation describes the ability of SSDs to permanently delete a file after they are removed from the file system.
And this brings us to the conclusion that file shredders are NOT needed for SSDs, in fact they could damage it. So when removing a file on an SSD drive, Permadelete simply deletes the file and does not overwrite it.
Permadelete has an auto-update functionality so it might ask you to let it connect to the internet. It's updating process is silent and hassle free, it also does not interrupt the users from what they are doing. We have tried our best to make the updater as efficient as possible. For example, it only downloads the files that are new and skips the old ones. Or, if something happened while downloading the files, next time it starts it will just continue from where it left it off, not from the beginning.