Cybercrime is a growing global problem that no company or country can tackle alone. At any given time, an estimated 150 000 viruses and other types of malicious code are circulating across the internet, infecting more than a million people every day. Anti-virus software developer McAfee counts 75 million unique pieces of malicious malware code on its databases, with botnets spewing out spam that account for a third of all the emails sent every day. Bots are one of the most sophisticated and popular types of cybercrime today. They allow hackers to take control of many computers at a time, and turn them into "zombie" computers, which operate as part of a powerful "botnet" to spread viruses, generate spam, and commit other types of online crime and fraud. The worldwide cost of cybercrime is estimated at over €750 billion annually in wasted time, lost business opportunities and the expense of fixing problems.