The best method to delete sensitive information from storage media that will be reused is multiple overwriting. This is because multiple overwriting ensures that the data is practically unrecoverable by any software or hardware means. Multiple overwriting involves writing 0s, 1s, or random patterns onto all sectors of the storage media several times, making the original data unreadable or inaccessible. There are various software programs available that can securely delete files from storage media using multiple overwriting techniques1.
Crypto-shredding is not the best method because it only works for encrypted data. Crypto-shredding involves deleting the encryption key used to encrypt the data, making the data unreadable and unrecoverable. However, if the data is not encrypted, crypto-shredding will not erase it2.
Reformatting and re-partitioning are not the best methods because they do not erase the data completely. Reformatting and re-partitioning only delete the file system structures and pointers that make the data accessible, but the data itself remains on the storage media and can be recovered using data recovery software