Ecommerce glossary

The terms are in alphabetical order, each with a short, general definition and a link where there is more to read. For whole topics, start with the guides.

Tax and legal entries are general information, not advice: confirm with an accountant before you act on them.

The card schemes' protocol for checking that the person paying is the cardholder, usually with a prompt in the bank's app or a one-time code. It is the method most used to meet Strong Customer Authentication in Europe.

A basket a shopper filled and then left without paying. Shops send reminder emails to win some of them back; on WhizzyCommerce, abandoned checkout emails are included on both plans.

Revenue divided by the number of orders over a period. Raising it, with bundles or a free-shipping threshold, grows sales without needing more visitors.

The address a page tells search engines is its main one, set with a canonical link tag in the page's head. It stops the same product, reached through several paths, filters or tracking parameters, being counted as duplicate pages.

In Portugal, invoices must be issued by software certified by the Tax Authority (AT) under Portaria 363/2010, and each one carries an ATCUD code and a QR code. WhizzyCommerce is not certified itself: certified invoices come from the merchant's own InvoiceXpress or Moloni account, see invoices.

A card payment reversed by the cardholder's bank after the shopper disputes it, for example as not received or not authorised. The merchant loses the amount and usually pays a fee, unless they win the dispute with evidence such as proof of delivery.

The steps between the basket and a paid order: contact details, delivery address, shipping method and payment. Every extra field or step loses some buyers, so short checkouts tend to convert better.

The share of visits that end in an order: orders divided by sessions, as a percentage. It is most useful compared with your own past figures and split by traffic source.

A document that cancels or reduces an invoice already issued, after a refund, a return or a mistake. It refers to the original invoice rather than editing or deleting it.

Portugal's national postal operator, Correios de Portugal, which delivers letters and parcels and runs the express service CTT Expresso.

A model where the shop sells products it does not stock: each order goes to a supplier, who ships straight to the customer. Less money is tied up in stock, but margins are thinner and delivery depends on the supplier.

Everything between a paid order and the parcel at the door: picking, packing, labelling, shipping and tracking. A shop can do it in-house or hand it to a third-party logistics provider (3PL).

The General Data Protection Regulation, EU Regulation 2016/679, which governs how the personal data of people in the EU is collected and used. A shop needs a lawful basis for each use of customer data, such as performing the contract, or consent for marketing emails.

The total value of goods sold through a shop or marketplace over a period, usually before refunds, fees and costs. It measures volume, not revenue or profit.

An architecture where the storefront shoppers see is built separately from the commerce back end and talks to it through an API. It gives full design freedom, at the cost of building and maintaining that front end yourself.

A website where many independent sellers list products while the operator runs the storefront and often takes the payment, such as Amazon or Etsy. Sellers gain reach, and in return pay commission and give up much of the customer relationship.

A Portuguese mobile payment app from SIBS. At checkout the shopper enters their phone number and approves the payment in the app on their phone.

An open protocol introduced by Anthropic in 2024 that lets AI assistants connect to tools and data in a standard way. On WhizzyCommerce, agents connect to a shop over MCP with named, scoped access, see AI ecommerce platform.

The legal seller in a transaction, in whose name the sale is made and who answers for its tax, refunds and chargebacks. On WhizzyCommerce the merchant is the merchant of record, paid through their own Stripe, PayPal or Mollie account.

Portugal's interbank network. Online, the shopper gets an entity and a reference and pays at an ATM or in home banking, often hours or days later, so the order waits for the payment. On WhizzyCommerce, Multibanco and MB WAY come through the ifthenpay plugin, see payments.

The EU's VAT One Stop Shop, in place since 1 July 2021. Once distance sales to consumers in other Member States pass the EUR 10,000 EU-wide threshold, VAT is due in each customer's country; OSS lets you register in one Member State and file one quarterly return for all of them. More in the OSS guide and the European Commission OSS guidance.

A company that processes online payments for a shop, accepting cards and other methods and paying the money out to the merchant, such as Stripe, PayPal, Mollie or ifthenpay. It charges its own fee per transaction, separate from any platform fee.

The Payment Card Industry Data Security Standard, the card industry's security rules for anyone who stores, processes or transmits card data. Letting the PSP collect card details on its own fields or pages keeps most card data out of the shop's systems.

The Standard Audit File for Tax, an XML file that Portuguese accounting and invoicing software exports for the Tax Authority (AT). Ask your accountant which periods and which software must produce it.

Stock keeping unit, a shop's own code for one sellable item. Each variant usually has its own SKU, so a T-shirt in three sizes is three SKUs.

A requirement of the EU's second Payment Services Directive (PSD2) for most online payments. The payer proves two of three things: knowledge (something they know, like a PIN), possession (something they have, like their phone) and inherence (something they are, like a fingerprint).

Machine-readable labels in a page's code, usually JSON-LD using the schema.org vocabulary, that tell search engines a page is a product with a price, stock and reviews. It can earn rich results, such as prices and stars, in search.

A charge taken on each sale, as a percentage, a fixed amount or both. Shops often pay two: the payment provider's and the platform's. WhizzyCommerce's is 2% of each paid sale on Free and 0.5% on Pro, see pricing.

One version of a product that differs by an option such as size or colour, with its own price, stock, SKU and pictures where needed.

The EU's consumption tax, charged on most sales and paid over to the state. Each Member State sets its own rates; the standard rate in mainland Portugal (IVA) is 23%.