The head of Europol says that the growth of cyber-crime is “relentless”. The agency has identified a range of increasingly common methods used by 21st Century offenders – and these are not sophisticated. These include digital payment attacks, ransomware, selling illicit material on the dark web and stealing people’s personal data to commit fraud or identity theft.

Much of the time, established criminals seek to enlist the services of unethical hackers and younger “script kiddies”, who use programs developed by others to infiltrate computer systems.

“The organised crime gangs are saying, ‘Show us how good you are’, and drawing them into the dark side,” says Alan Woodward at the University of Surrey, who is an adviser to Europol.

“They don’t have the technical capability [themselves], they’re switching from drug trafficking and all the rest of it to cyber-crime because basically there’s a much better return on it.”

The ways in which young people become involved in this sort of activity were recently detailed in a report by the UK’s National Crime Agency (NCA). The average age of those arrested for malicious hacking activities was just 17 – the offences included vandalising websites, stealing data and breaking in to private computers.

Because our world is so much more connected than ever before, and those connections are often woefully insecure, it’s relatively easy to find ways of exploiting computer systems illegally. And ransomware in general is increasingly successful. In 2016, criminals made an average of $1,077 with every attack. For the BBC's Cyber-hacks series, Click's Spencer Kelly discovered how cyber-criminals can acquire off-the-shelf ransomware using only a search engine.

As Woodward points out, the easiest thing to do is “just cast it out there” – whether it’s ransomware, spyware or spam – and see what comes back.