Over the last few years, in a predictable tide of announcement, anticipation and launch, Apple has released successive operating systems (A.K.A. macOS) for its Macintosh line of computers. Each year these new versions improve performance and reduce the overhead of existing features, as well as add additional features to take advantage of new technologies.
If the computer is like a car, then the operating system is like the steering wheel, pedals and gauges. It is how we interface with the car, how we input our desires, and then how the computer gives us feedback on our inputs.
Like deer caught in the headlights of the aforementioned car, this often leaves people very confused about whether to upgrade. On one hand, we’re told that the operating system needs to be updated in order to get security updates, and on the other we’re concerned about “slowing down” our computer, especially if it's getting long in the tooth.