Signals in the context of audiences in Google Ads are the traits of audiences or the context of the user, for suppose from which device they are viewing, what is their geographical location, or the search topic & terms they have searched, their behavior in the website etc. Signal is used by Google Ads algorithm to find the right audience to increase your ad conversion rate or reach the required goal.

First-party data is one example of Google Audience Signal. Geographical location is another example of a google signal. All the user behaviors, traits and ad personalization preferences of the user stored anonymously on Google Ads are the examples of Google Signal.

When it comes to audience signals in Google's Performance Max Campaign, they are basically categorized into Demographic, Interest-based, Behavioral & Remarketing Signals. In Performance Max, there are seven types of audiences. They are Your data segment (earlier remarketing list), Affinity segment (earlier affinity audience), In-market segment (earlier in-market audience), Similar segment (earlier similar audiences), Detailed demographic segment (earlier Detailed demographics (audience)), Custom segment (earlier custom audience), and Life-event segment (earlier life-event audience).

In-market audience signals help the algorithm identify the target audience who exhibit high intention to buy. You can view the insights of the in-market audience segment you select in the Performance Max campaign while setting up.