Think about it this way: When people are actively seeking out your business, products or services, they commonly do so using the Google Search Network.
In the opposite situation – where you are trying to spread the word about those products or services to people as they browse the Internet – you will use the Display Network. Both tools accomplish the same result, but the person using the tool changes depending on the situation.
Ninety percent of people on the internet are reached via the Google Display Network. With two million plus websites, display campaigns can reach people while they are using sites like YouTube, Gmail and other applications.