How do I keep my laptop virus-free?
No matter how careful you are with what you download or click, your computer is an easy target for old-school viruses that erase data, or more cutting-edge attacks like ransomware — programs that demand money in order to restore access to your suddenly walled-off hard drive. Mac users can get by with occasional checkups using Bitdefender's Virus Scanner (free; bitdefender.com). For PCs, the best defense is McAfee's LiveSafe ($80 a year; mcafeelivesafe.com), which will block viruses and warn you about risky websites.
Expert Tip: Activate two-factor authentication for financial accounts to thwart Trojan viruses that steal passwords.