One quotable definition per term, then what it means for a small cross-border seller.
A lightweight ecommerce website builder is a hosted, no-code tool for creating an online store that deliberately limits its feature set to what a small seller needs: a small product catalog, a storefront, checkout and basic orders, at a low fixed cost and without server maintenance.
A platform transaction fee is a percentage of each order that an ecommerce platform charges for its own account, on top of the subscription price and separate from the processing fee charged by the payment gateway.
Cross-border ecommerce is the sale of goods online from a seller in one country to consumers located in another country, typically through the seller's own online store or a marketplace.
An SKU (stock keeping unit) is a unique identifier for one sellable item in a catalog, including its specific variant such as size or colour; a product with three sizes and two colours is six SKUs.
A payment gateway is the service that securely captures a buyer's payment details at checkout, authorizes the transaction with the card network or wallet, and settles the funds to the seller, charging a processing fee for doing so.
Product testing in ecommerce is the practice of listing a small number of candidate products and driving paid traffic, usually from TikTok or Facebook ads, to measure which ones sell before investing in inventory, content and scale.