Showing the differences and similarities between Cascade and Niagara
The Niagara Editor is one of two tools you can use to create and adjust visual effects inside Unreal Engine 4 (UE4). Before Niagara, the primary way to create and edit visual effects in UE4 was to use Cascade. While Niagara does have many of the same of particle manipulation methods that Cascade offers, the manner in which you interact and build visual effects with Niagara is vastly different.
This page links to documentation regarding the Niagara effects system, including information about the Emitter Editor, the System Editor, and more. If you are new to Niagara, it is recommended that you check out the Getting Started section which includes a high-level overview of the Niagara Editor. You can also check out the Guides section, which has How-To articles on various tasks.