Getting confused about the piles of development tools that people use for Javascript? Here's a quick index of what is used for what.
Keep in mind that you shouldn't add tools to your workflow for the sake of it. While you'll see many production systems using a wide range of tools, these tools are typically used because they solved a concrete problem for the developers working on it. You should not add tools to your project unless you have a concrete problem that they can solve; none of the tools here are required.
Start with nothing, and add tools as needed. This will keep you from getting lost in an incomprehensible pile of tooling.
Typical examples: Gulp, Grunt