The core of FACTS is to construct a Facts Content Incentive Mechanism that is based on the block chain technology, i.e. the Proof of Facts (PoF), and hence to form an authentic content library that is based on Facts Graph. The Facts Content Incentive Mechanism and Facts Graph of FACTS are open to all content class DAPPs via a uniform interface to form a vertical public block chain of service content ecology. The facts incentive mechanism is designed in accordance with the authentic content views of neutrality and verifiability, any authentic content is proved authentic by referencing or depending on other reasonable facts bases, and the Content Review Panel guarantees the mecha— nism is executed properly to ensure the quality of Facts Graph. FACTS Index is a core parameter reflecting the authenticity of content to let users know at a glance.