Glossaryad networksprogrammatic advertising

Ad Network

remnant inventorypremium inventorypublisheradvertiserad impressionnon-premium inventory

An ad network is a technology platform that acts as a broker between a group of publishers and a group of advertisers, connecting supply and demand across the digital advertising ecosystem.

Traditionally, ad networks worked by aggregating unsold ad inventory from multiple publishers and offering that pooled set of impressions to advertisers at prices well below what a publisher would charge through a direct sale. This type of inventory became commonly known as non-premium, or remnant inventory — space that publishers couldn't sell directly and were willing to offload at a discount.

Today, many ad networks handle both remnant inventory and premium inventory, operating across all types of media and channels — from display and video to mobile and connected TV.

AdNetwork_example

Inventory
Also known as: ad inventory, ad space Ad inventory refers to all available ad space on a given site. The terms "inventory" and "ad space" are often used interchangeably in the industry. Inventory is typically divided…
Top Ad Networks and Mobile Ad Networks: A Reference Directory
Ad networks were among the first pieces of advertising technology introduced in the mid-1990s. They helped publishers sell available ad space to multiple advertisers, allowing buyers to purchase inventory from many…
Remnant Inventory
Also known as: unsold inventory Remnant inventory is ad inventory that a publisher was unable to sell through its direct sales channels or premium campaigns. Rather than leave those impressions unfilled, publishers…
Ad Unit
Also known as: ad placement A single unit of ad space available on a publisher's website or mobile app. Ad units represent the discrete slots into which advertisers serve creative — a banner position at the top of a…