Paid link
A paid link is a link you get in return for money, products or a service. Search engines expect it to be marked as sponsored.
A paid link is a link you get in return for something: money, free products, a discount or a service. Sponsored posts, affiliate links and advertorials all carry paid links. They're a normal part of marketing. The trouble starts when they're passed off as links the site chose to give.
What Google expects
Google is fine with paid links as long as they're marked. You add rel="sponsored" to the link, or rel="nofollow", so search engines know not to count it as a vote for your page. Google explains how in its guide to qualifying outbound links.
An unmarked paid link is link spam under Google's spam policies. The site that sells it and the site that buys it both take the risk.
For example, say Harrow & Pine sends a free armchair to an interiors blogger, who writes a review and links to the chair's page. That's a paid link, because the chair was the payment. If the link carries rel="sponsored" and the post says the chair was a gift, everyone has played by the rules.
Paid placement and AI answers
Some sites sell places in their "best of" lists. That's a paid link with extra steps, and it works on AI platforms too, because they often read list articles before they answer. Many of these deals are hard to tell apart from an honest review, which is part of why they work.
They also carry more risk than they used to. Lists that rank anyone who pays tend to lose readers' trust, and Google's policies treat a page made mainly to sell links as spam. A brand that's named because it earned its place is easier to keep there.
In AnswerOrbit
In Recommendations, we never suggest links you pay or trade for, or reviews you arrange or reward. We do suggest getting onto pages that name your competitors and not you, by asking the publisher, getting listed in a directory or growing your reviews.