Collections are a way to group your assets together.
This can help with two things:
1. Keeping your assets organized as you start uploading more things to Marpipe
2. Help you understand the performance of larger themes as a whole in your advertising.
For example, maybe you have images that feature a testimonial, and copy that quotes the user. You can create a Collection called "Testimonials" and house both the image and the text in there.
You can organize them however works best for your situation.
How to Create a New Collection
You can get to the Collection area when you're in Assets by looking in the upper left hand corner for the Collection tab.
Click "Add New Collection" button and input the name of your collection.
Click the three dots under the Collection you want to edit, and click "Edit Collection."