Collections are a small sampling of 5-10 products.Every collection is a focused set of posts on a particular topic, providing an easy way for you to organize all the things you’re into. Each collection can be shared publicly, privately, or with a custom set of people.Collections is a "catalog of ideas, that inspires visitors to "go out and do that thing.Collections are a way of visual discovery of themes and ideas.
Collections are for showcasing designs. Some have used them to showcase sets for Holidays, Weddings, etc. Collections can be shown on Profile, Storefronts, Pinned, Shared on blogs, etc. Collections can be set up how you wish them to be and you have more control over how you wish products to appear.