Upgrading from OS X 10.9.5
I have a MAC Desktop (27") and Laptop. Both operate with the OS X 10.9.5 system. I am now trying to use software that won't operate on anything below OS X 10.10. I can't for the life of me figure out how to upgrade, or even what I am supposed to be upgrading to (there are far too many options when I look at the Apple site.
MacBook