What makes the macintosh operating system safer than a windows operating system?

Nothing. The fact is, there are far less macs out there. People who write malware are out to attack the masses. If mac ever becomes half as popular as windows, malware will be coming out of the woodwork. Out of every 100 computers sold, 95 are PCs and it has been this way for over 30 years. People who know computers don't squander hard earned money on Macs knowing they are three times the cost of a comparable PC and aren't compatible with 95% of the software on the market.