Social proof is a concept from psychology and describes the influence that the opinions and actions of other people have on our own decisions. In particular, social proof refers to how we behave in social situations when we are unsure of what the "right" behaviour is.

In the marketing world, social proof refers to the use of positive reviews, testimonials, recommendations and other forms of endorsement to persuade potential customers to buy a product or service. The aim of social proof is to build trust and credibility in a brand or product by showing that it is positively rated or used by other people.

There are different types of social proof, such as expert reviews, customer reviews, number of downloads or sales, recommendations from celebrities or influencers, awards and certifications. Companies can use social proof in their marketing efforts to gain the trust of potential customers and lead them to conversion.