From a shopper's point of view, VAT (value-added tax) and sales tax look almost identical: a percentage gets added to the price at the register. The real difference is invisible to the end buyer -- it's in how the tax is collected across the supply chain before the product ever reaches you.
Sales tax: collected once, at the end
Sales tax, used in the United States, is charged only at the final retail sale to the end consumer. Businesses further up the supply chain (manufacturers, wholesalers) generally don't pay sales tax on materials and goods intended for resale -- the tax is designed to apply once, at the last transaction.
VAT: collected in stages, credited back
VAT, used across most of the world including the EU, UK, and many other countries, is charged at every stage of production and distribution -- but each business in the chain can typically reclaim the VAT it paid on its own inputs, so only the value it added gets taxed at that stage. By the time the product reaches the end consumer, the cumulative VAT collected equals roughly the same percentage of the final price as a single-stage sales tax would -- the multi-stage collection is mostly a matter of how governments track and collect it, not a fundamentally different final cost to the buyer.
Why this matters if you sell internationally
If you're pricing a product for a country with VAT versus a U.S. state with sales tax, the compliance obligations are different even when the visible price impact to the customer looks similar -- VAT registration thresholds, invoicing requirements, and reclaim mechanics vary a lot by country and are worth checking directly for your specific situation rather than assuming sales-tax rules carry over.