Consumer Reports has named the four major online threats you need to defend against. Viruses and worms can destroy information on your hard drive, clog the network, and leave hackers a back door to turn your PC into a spam-sending zombie. Spyware tracks your mouse movements and keystrokes, and transmits that information to thieves who can use it to steal your money or your identity. Spam is often offensive, opening companies up to lawsuits, and it is frequently used by hackers seeking a toehold in company networks.”]
Source: https://www.bankinfosecurity.com/major-online-threats-exposed-a-42