Sometimes the items you want your users to search for will have more than one type, or variant. For example, a t-shirt may be available in multiple colors. In these cases you'll likely want a separate record for each of these variants.
This isn't something you can configure in Algolia directly. You'll need to handle this when you send your data to Algolia for indexing. We have an article on this topic here.
If you use a specific implementation like Shopify, it will index the variants for you.