There are three main types of malware: viruses, worms, and Trojan horses. As the Mac OS becomes more popular, hackers and malware developers will undoubtedly begin to target the platform more and more. to be one of the fastest growing, leaving the company just shy of 10 percent market share by some estimates. Recent reports have shown Apple's market share in the U.S. Though it is true that OS X has been relatively free of viruses and other malware, in large part this has been because the small Mac market share has made the platform an insignificant target for malware developers however, the landscape is steadily changing. Readers periodically ask about antivirus recommendations for OS X, especially given some of the past rhetoric about Macs not having any viruses.