Third parties are security holes

First party data is data your company has collected directly from your audience, whether customer, site visitors, or social media followers.

Second party data is information you didn't collect yourself — in other words; you're using it secondhand. Businesses often get it by working with a trusted partner that shares audience insights in a mutually beneficial relationship.

Third party data is any data collected by a business without any direct link to your business or audience. Its scope is much wider than first and second party data.