What is the difference between managed and automatic placements?

Ans. The Display network includes both automated and controlled placements. Marketers may use managed
placements to select from a variety of alternatives for displaying their Google AdWords ad. Specific websites, locations, videos, apps, and so on are examples of these options.

For example, if a specific website scores well for a collection of your selected keywords, you may opt to display your Ads just on those pages. There are no alternatives in automated placements, and your advertising are shown automatically.