A smart collection is a grouping of products defined by rules that are set by the merchant. Shopify automatically changes the contents of a smart collection based on the rules. Smart collections, like other types of collections, are used to break down the catalog of products into categories and make the shop easier to browse.
By default, a store can have up to 5000 smart collections.
The Collect resource is used to connect a product to a smart collection. However, these collects can't be added or removed from the API as they're managed by the rules of the smart collection.
You can use the CustomCollection resource to work with collections where each product in the collection is manually chosen by the merchant.
What you can do with SmartCollection
The Shopify API lets