Botnets can send spam and flood Web sites with countless requests for information, a cyber attack also known as distributed denial of service.

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Those included posting private data, including credit-card and Social Security numbers, of Web users and launching distributed denial-of-service (DDoS) attacks against media sites who posted stories they didn't like.

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Russian hackers, meanwhile, took to the Net, launching waves of distributed denial-of-service attacks against the country's government, banking and media Web sites, using thousands of personal computers hijacked with hidden software to overload the servers.

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Security experts say the attack uses more sophisticated techniques than most DDOS (distributed denial of service) attacks and targets the Web's infrastructure, which has led to other sites performing slowly.

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Security experts said the attack used more sophisticated techniques than most distributed denial of service, or DDoS, attacks and targeted the Web's infrastructure, which led to other sites performing slowly.

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