What is an AD GROUP?
Ad groups are groups of ads that are similar. Within one campaign, you can have multiple ad groups. For example, if your ad campaign is to advertise your dessert business, you might have one ad group for cookies, one ad group for brownies, one ad group for cake, etc.
Why split your campaign into AD GROUPS?
Each ad group can be targeted to a different audience using different keywords. In an NRB ad campaign, different ad groups can be geo-targeted to people living in different countries.
Generally, ad groups help you optimise your campaign to get the best return on your advertising spend.