An ad network is like a matchmaking service for advertisers and website owners. It connects advertisers who want to promote their products or services with website owners who have space available to display ads. Ad networks act as middlemen, helping advertisers find the right audience and website owners earn money from their online content. They handle the technical side of things, such as ad placement and tracking, making it easier for both advertisers and website owners to work together. In simpler terms, an ad network brings advertisers and website owners together to make sure the right ads are shown in the right places.