Is your Mac acting kind of…weird? Whether you’re seeing adverts you can’t explain, or your system is unreasonably slow, you might think the problem is malware. And you might be right (but probably aren’t). Back in 2009 my co-worker Jackson asked whether Macs need virus scanners. The common consensus at the time was “no”, but Macs have grown in popularity since then – and not surprisingly, so has Mac malware.