Serenity Caldwell writing for iMore in 2017: The problem: Mac malware in the Library folder
There are things you can do without having to burn it all down. It happens to the best of us (not me, of course). If your Mac is running slow or you're seeing unusual advertisements within your web browser you might have accidentally installed malware at some point.
Though it's not easy to hack into or break through a Mac's security, it is possible, especially if someone accidentally installs malware without realizing it.
