We are surrounded by digital data. Each time you watch a video, read something online or receive an email, you consume data created by others. And each time you text someone, work on a document on a computer or post something on social media, you create your own data.
In an increasingly connected world, this data is a valuable commodity. It is collected, analyzed and used for various purposes, from selling you things online to trying to steal your money. Knowing how to protect your most valuable data requires understanding what data is, how it is created and discarded, and who is after it.
What is digital data
Any information processed or stored by a computer, smartphone or data storage device is digital data. You create and consume this information in the form of text documents, videos, sounds, images, software, etc. At its most basic level, however, all this data consists of sequences of ones and zeros, known as binary data.
Because all computers and smartphones use this format, digital data can be created, processed and stored on any such device. It can also be transferred from one device to another or made available to millions of other users online.
Some of your personal data is particularly important to keep safe. Examples include your date of birth, address, passport number, driver’s license number, social security number, bank account number, health records, etc. Any data that could potentially be used to identify you is known as personally identifiable information.
Creating digital data
Each time you use a computer or mobile device, you create data. You can easily see some of this data, such as, for instance, when you create a new Word document, post something on social media, or take a picture on your mobile phone.
But most of the data you generate each time you use a digital device is much harder to see. For instance, your computer keeps a detailed record of when you use it, which apps you use and for how long. If you are an average user, your Internet browser tracks websites you use, time you spend on each of them, each single click you make and each single file you download. For each photo you take, your smartphone records when and where you take it. Unless you know where to look for this data, it remains hidden from your eyes.
Discarding digital data
Discarding data is not as straightforward as it appears. When you click “Delete” or move a file to a Recycle Bin (for Windows users) or Trash (for Apple product users), your operating system keeps the file there for some time in case you change your mind. Anyone can easily find this file if they have access to your device.
But even when you empty the Recycle Bin (or Trash) or when you delete files bypassing the Recycle Bin, these files do not just disappear from your device. When you delete files in this way, the operating system on your device receives a signal that these files are no longer needed and stops showing them. The operating system does not really make these files disappear. It marks the space they hold on your device’s hard drive as available and, only when this space is needed for something else, your operating system overwrites the binary data of the files you have deleted with new data. Until that happens, the “deleted” files stay on your device. It is not too difficult to recover them.
There are special tools that you can use to securely wipe files from your devices, that is, to delete them and replace their binary data with random combinations of ones and zeros. Follow these directions to install and start using BleachBit, a free tool that wipes data from your hard drive securely and permanently.
It is much harder to discard data that you have shared online. When you post photos on social media, sign up for services with your email address, share documents through messaging apps or send videos through file-sharing sites, you cannot always track who has copies of this data.
Who is after your data
You can never know who might be interested in the data you have on your devices. Individuals, groups or organizations might want to get access to this data for a number of reasons, such as, for instance, to steal your online banking credentials or personal photos and videos to blackmail you. Because you do not know who might be interested in your information and why, you should always ensure that all the computers, mobile devices and data storage devices are safe and secure.
There is also a lot of information you leave behind when browsing the internet on your computer or mobile device. Make sure you understand what kind of information you reveal by being online, how this information is being used, and what you can do to minimize your online footprint.