Digital freedom fighters or computer-based criminals, hackers garner mixed reactions depending on what they do and why they're doing it. But in this video, Keren Elazari suggests that we should perhaps think of all hackers as the Internet's immune system.

Sure, some hackers do good and others do bad, but by and large they all expose vulnerabilities that have to be fixed, Elazari reckons. In other words, they push the internet to evolve and improve, to grow stronger and healthier. Reckon she's onto something? [TED]