Digital devices such as PCs and smartphones are essential in both work and daily life. That’s why, when you replace, dispose of, sell, or hand over a device, it’s critical to handle stored data properly.
This article explains how data erasure software removes data and how it differs from common actions such as deletion and factory reset.
What is data erasure?
Data erasure is the process of making information stored on media (HDDs, SSDs, smartphones, etc.) unreadable by any means—even if a third party uses specialized recovery tools.
“Deleting data” is not the same as “erasing data”
These terms are often confused, but they are different in most cases.
Deletion / reset (factory reset)
With typical deletion, the data often becomes “invisible” to the OS, but it may still remain on the storage until new data overwrites it. In some cases, specialized recovery software can restore it.
Data erasure
Data erasure writes a fixed pattern (e.g., zeros) or random data to the storage area one or multiple times so the original content cannot be read back. This physically invalidates previously stored information.
The risk of relying on “factory reset”
Many people assume a reset fully removes data and then resell or transfer a device. However, if the data is recoverable, personal and confidential information can leak.
Potentially exposed data includes names, addresses, phone numbers, credit-card information, online banking/SNS passwords, purchase history, location history, and (for corporate devices) customer data or confidential business documents.
A well-known example is the 2019 incident in Kanagawa Prefecture involving resale of HDDs and data leakage:
https://www.masamune.com/news/2019hdd/
Data erasure algorithms
There are multiple erasure algorithms with different trade-offs (speed vs. assurance). The right method depends on the sensitivity of the stored data and your security requirements.
For details on erasure levels and algorithms:
https://www.masamune.com/news/data-erase-level/
Summary
Deleting files or performing a reset is often not enough when disposing of devices containing personal or confidential information. Consider data erasure software (or physical destruction when appropriate).
MASAMUNE Erasure is designed and developed in Japan and is used by major organizations. If you’d like help choosing an appropriate method for your workflow, please contact us:
