Inventory Management
Inventory tracking is the setting that tells Shopify whether it should keep count of stock for a specific product variant at all.
In Shopify, tracking inventory isn't automatic for every product. Each variant has a setting that decides whether Shopify keeps a running stock count for it or just ignores quantity entirely.
For plenty of products, that's exactly right. Digital downloads, made-to-order items, and services don't have a physical stock count to track, so tracking stays off on purpose.
The trouble is when tracking gets switched off on a normal physical product, usually by accident, and nobody notices for months. Once that happens, Shopify has no idea how much of that item you actually have. It won't warn you when you're low. It won't stop you from selling something you don't have.
Ghost Stock flags variants with tracking disabled so you can take a quick look. If it's intentional, there's nothing to do. If it was switched off by mistake on something you sell physically, that's worth fixing before it causes a stockout nobody saw coming.