While guides can contain wildly disparate products, they’re mostly built on the same elements: a photo of the gift, a link to buy it, and maybe an explanation of its greatness. Often, you’ll find a small disclaimer along the lines of “All of our gifts are selected independently, and we may earn a commission if you shop through our links.”

It’s not that most writers, editors, and influencers in 2019 have any particular passion for picking out new pajamas for your sister’s kids. Instead, the internet has become a place largely fueled by shopping. Mostly unbeknownst to shoppers, purchase dollars from gift guides are often divvied up behind the scenes. A portion is kicked back to their digital inspiration, even if you wait a few weeks to buy something. To get a share of that cash, the gift guide has expanded to fit every corner of the digital economy, pitting disparate factions of the internet against one another in a competition to recommend a new tie your dad will actually like.

The term gift guide can refer to almost any collection of purchase recommendations, which can be delivered in a zillion different ways—a slideshow on a website, a series of embedded links in a YouTube video, a bunch of Instagram Stories saved as a “highlight” on a model’s profile page. Newspapers and magazines have been providing holiday selections to their readers for generations. The Neiman Marcus Christmas Book, arguably America’s most well-known luxury gift guide, took its current form in 1959 to answer queries the company fielded every year from journalists looking for its most outrageous presents, such as $1.5 million rose-gold private planes and a pair of $900,000 his-and-hers Rolls Royces.

Part of my own holiday mandate at PurseBlog was collecting the internet’s most useless and expensive tchotchkes—a quarter-million-dollar Baccarat chandelier or a $70,000 foosball table swathed in Hermes leather—and playfully threatening to guillotine the people who could afford them. (Many of those same people were readers, laughing along with me, but for different reasons.)

Holiday press coverage is so powerful that even this kind of wealth-rubbernecking and joke-cracking is courted by brands. Being written about in almost any capacity is a much more effective vehicle to capture attention than simply being seen in an advertisement. James Nord, the founder and CEO of Fohr Card, an agency that helps influencers find and negotiate ad campaigns with brands, thinks the gift-guide format has been so widely adopted by publishers and advertisers alike because it serves both masters: It attracts readers and turns them into buyers.

Nord likens a recommendation from a popular writer or influencer to a tip from your coolest friend. “A person who can deliver a message and create action is so much more valuable than someone who can just deliver the message,” he says. The recommendations or endorsements of internet personalities who have gained the trust of their audiences can have a profound effect: The Instagram star Danielle Bernstein once sold more than $1 million of bathing suits in three hours.