Scripts are just like plugins in the sense that they are created with a programming language. However instead of customizing the software like a plugin does, a script automates a process or execution within the software. In short, if you have to click it in After Effects there's probably a script that can help you automate a process. So if you find yourself doing something over and over again there's probably a script for that. As you get more comfortable with After Effects you’ll find that utilizing scripts can help you just as much as plugins. I personally use scripts more than plugins, but both are useful in their own way.
Unmult Plugin After Effects
41 Free After Effects Plugins. The Red Giant Knoll Unmult free plugin is a simple but incredibly powerful plugin. Unmelt creates an alpha channel from any image shot on black. According to Red Giant “Unmult is particularly useful for generating alpha channels for flares rendered on black or video or filmed media that is shot on black like cloud tank. It’s important to note that After Effects comes with a motion blur plugin called CC Force Motion Blur but it’s a real render hog, slowing your workflow to a virtual standstill. RSMB is very lightweight and the results are impressive! Knoll UnMult. Knoll Unmult is a free plugin that can be downloaded from Red Giant Software.