Stacks (formerly Blockstack) seeks to power a new type of decentralized internet that would give users more control over their data and make censorship of content more difficult.
It has properties like "built-in privacy" where data in the Stacks app (e.g. photos, messages, health records) is encrypted by default. Apps will not be able to view, access or track your activity. The user, not the app, owns 100% of all data. Additionally, users are free to move their data as well as transact and transfer your assets - without any app or company permission.
Based on its programming language Clarity, Stacks' smart contracts can create, own and trade new types of digital assets such as tokens and digital collectibles. By using the Stacks app, creators can also share the value they create.
Stacks uses a hybrid consensus mechanism, which Stacks calls Proof of Transfer (PoX).