Unlike Plug-ins, Extensions or other External Image Editing Softwares, Lightroom Presets are already a built-in feature of LR. If you are not using Presets to help speed up and streamline your editing, you're missing out on a huge trick.
Lightroom Presets are saved settings that allow you to apply an edit to your image in one click.
Lightroom comes with the capability to 'save' specific develop settings as a Preset. You can then apply this preset every time you wish to recreate these steps on a new image. LSP Lightroom Presets take this not just one step further, but in leaps and bounds to make sure you never have a bad editing day again. The LSP presets are designed to be mixed 'n matched together for infinite possibilities. The specific blends and mixes of settings use mean you can find the perfect look for you image in just a few clicks, each edit will be unique depending on your tastes and style.
You can also hop over and make tweaks and changed yourself as you go for a double-whammy of editing awesomeness. Once you install your LSP Presets into Lightroom, they will always be there for you whenever you wish to use them. You can use LSP Actions for a complete edit, a part edit or only sometimes - it's up to you!
Lightroom Brushes are similar to presets but rather than effecting your whole image, you can select a brush and paint it just over a single area (such as face or clouds). Lightroom brushes are currently only able to be used with Lightroom CC Classic or Lightroom CS4-6 as other versions do not have the capability of saving a brush preset.