The rise in the amount of personal data we're all producing, combined with the hunger of online crooks to seize on any information they can exploit for their own benefit, has created an "explosive combination" that is putting our privacy at risk.
Whether it's via your smartphone, your web browser or your applications, data about you is being produced all the time. In some cases, you're explicitly producing it yourself, perhaps by posting on social media, while in other cases it's because metadata about how you move around the web is being collected and sent to big tech companies, their advertisers and others.
In some cases, people are aware that information is being shared, because they've shared it themselves, while they might be less clear about how data about their activity on the web is being collected – if they're even aware it's being collected at all.
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Because not only is there the risk that corporations could paint an intimate picture of your demographics, interests and fears, the more data that's produced the more that's available to be mined and harnessed – and not just by multinationals and governments, but cyber criminals too.
Personal data, in particular, is extremely cheap, so you can buy somebody's file for a few dollars, Carissa Véliz, associate professor at the Faculty of Philosophy and the Institute for Ethics in AI at the University of Oxford, and author of Privacy is Power: Why and How You Should Take Back Control of Your Data, told ZDNet Security Update.
On the other hand, personal data is extremely valuable because if you have lots of it, you can become extremely rich, she says: "And third, it's very dangerous because it's very sensitive and it's easy to misuse it".
For example, it's entirely possible for a dark web cyber criminal to buy stolen bank details and other personal information for a very low price, then use that information to commit identity theft – and in the name of someone else who won't realise what's happened until it's too late. That type of situation can have long-term consequences.
"This is a crime that is going up exponentially, because more people are using tech all the time and that means that somebody can use your identity to commit crimes in your name," said Véliz.
"Even simple cases can make your life really difficult because if somebody takes your name and takes out a phone contract and then doesn't pay back, that can be enough to ruin your credit score," she added.
But it's not necessarily just criminals who can exploit personal data shared on the internet – governments could abuse it in order to identity activists and other individuals deemed a nuisance in an attempt to clamp down on them.
"We are building an architecture of surveillance that could really sustain a dictatorial regime and I worry a lot about that because democracy is fragile and we have to reinvent it and defend it every single day day – and an architecture of surveillance isn't going to support it very well," said Véliz. "We should care about privacy, because privacy protects us from abuses of power, both individual and as a collective."
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There are steps that individuals can take to improve their online privacy, such as sticking to using devices and apps that don't track personal data and being careful about what information to share online – and it's possible to delete old data as well as restricting what new data you put online.
"The most valuable personal data will always be the most recent, and so we always have an opportunity to start now. Now is a very, very good time to start," said Véliz.
"It's never too late because every every data point that you protect can save you from a case of identity theft or discrimination or extortion, and you might not know it."