My job involves taking countless screen captures every week, and of all the tools and utilities I've tried -- even the tools built into macOS -- nothing comes close to the power and flexibility of SnagIt. I've used it to take literally thousands of screen captures across a whole range of systems.
Not only does this tool allow me to capture all sorts of screenshots -- from simple captures to complex stuff like scrolling windows and such -- it also features powerful editing tools to help me get those screen captures ready for posting on the web or putting into publications.