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What is ransomware?

Computer viruses that threaten to delete your files unless you pay a ransom are known as ransomware.

Security experts have warned that ransomware is the fastest growing form of computer virus.

Like other computer viruses, it usually finds its way onto a device by exploiting a security hole in vulnerable software or by tricking somebody into installing it.

BBC Technology reporter Zoe Kleinman explains what ransomware does.

Read the full story:The computer virus that blackmails you

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