Cross-selling is a marketing tactic that marketers use to increase their product sales. When websites have products from multiple categories, they often employ Artificial Intelligence to provide a product suggestion that goes well with the product that the customer is buying.
These suggested products are either products of higher quality or of products that are complementary to the ones that customers are buying. For instance, if the customer is buying a single-side print label, the website will suggest a sticker design that goes well or an offer of bulk purchase that can be availed at lesser prices.
With these tactics, customers might go with the suggestion and those suggestions are called cross-selling or up-selling.