How do you clear all files off a laptop?

Go to the files you want to delete and click delete that will send them to the recycling bin. Delete them from there and they're out of the way. The good side about this is that if you suddenly need the file again you can access it but if you want to fully wipe it you will need to get the special software for that.

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Alternate Answer

Deleting from the recycle bin usually does not remove files from a drive permanently or forever. "Deleting" is a rather basic function that removes the addresses of files from certain directories, so that YOU cannot access them. Many files may remain on the drive, even if you cannot see them. The memory the old files occupy is available for future files, but it is there until over-written.

It is elementary to search such a drive and recover files or parts of files that are still physically present. In order to really wipe a drive clean of unwanted files, you have to use software that is designed to do this. Even wiping a drive clean is not a guarantee that information cannot ever be recovered with some very powerful and sophisticated procedures. Software packages offer various levels of security against file recovery by offering options of how many erasing passes will be made, and what if anything the memory will be 'filled' with during erasing. You might re-write files with 010101, for example, or random digits. If you are concerned about complete security against data recovery, NEVER rely on deleting. Deleting is almost no more sophisticated than a basic convenience for the user.