CleanShot X
There are a lot of options for screenshot utilities on the Mac, from the built in ability to capture images that's built in to the OS, to the full featured freemium app Shottr by indie developer Electric Endeavors for still images to even more powerful still and video capture products like SnagIt by TechSmith. The product I personally use, CleanShot X hits the sweet spot in the middle. It may be over kill if you just need to screenshot memes for social media, but if you are a blogger, need screenshots for work documents or deal with tech support regularly, you should take advantage of the 30-day money back guarantee and try it out.
CleanShot X has over 50 features, including several new ones in the just released version, 4.7:
Annotation
CleanShot Cloud uploads
Scrolling capture in any app
Screen recording with built-in camera overlay
Background tool (with new and custom background presets)
Text recognition (with automated cursor sizing)
Pin screenshots (and toggle them visible/invisible)
Hide icons and widgets
Self-timer
New Features in version 4.7 include:
Ability to resize screen shots
Cursor automatically resizes to match text found in the image
10 new background gradients wallpapers, as well as custom wallpapers
Saved presets for screenshots
Autoformats text when entered on a screenshot
Hide desktop now hides widgets too
Pinned screenshots can be toggled visible and hidden
CleanShot X is $29 for the current version with one year of updates and 1GB of cloud storage. If you need pro features like availability on multiple machines, guaranteed perpetual updates, unlimited cloud storage, custom domain association - a pro version is available for $10 a month, $8 a month if paid annually. CleanShot X is available as part of SetApp.