Lookalike targeting is often leveraged when you have defined a set of high-value customers as a Quora audience and would like to find more people like them on Quora. Lookalike targeting is a method that takes this existing audience and uses machine learning methods to find new people who have similar characteristics and activity on Quora. This new lookalike audience may have a higher likelihood of also being potential high-value customers as a result and can be used like any other audience for ad set targeting.
In order to create a Lookalike Audience for targeting, you need to have created an existing audience either using the Quora pixel (Website Traffic Audience) or uploading a List Match audience. You can then start the Lookalike Audience creation process on the Audiences tab by clicking "Create Audience" and choosing "Lookalike."