Inventory

Inventory is the goods (or bookable units) a business can sell. In e-commerce, it also means the record that says how many are left: on the shelf, in a warehouse, or already in someone’s checkout.

When the website, POS, and warehouse don’t share that number, you oversell, disappoint buyers, and create support tickets. Platforms like Shopify and WooCommerce keep catalog quantities; an API or CRM connection keeps other tools in sync. Accurate inventory is a digital asset, not a spreadsheet you update “when you remember.”

A real-life example of inventory

A rental shop lists three bikes as available. Two are already reserved from a phone call that never hit the site. The third customer books online, shows up, and leaves angry. That’s an inventory gap — the same problem as an online store that sells a size that isn’t in the box.

Keep one source of truth and update it when a sale happens. For how tools should talk to each other, see What Is an API? and the storefront side in Guide to Choosing the Perfect Website.