The InterPlanetary File System (IPFS) is a protocol and peer-to-peer network for storing and sharing data in a distributed file system. IPFS uses content-addressing to uniquely identify each file in a global namespace connecting all computing devices.
IPFS allows users to host and receive content in a manner similar to BitTorrent. As opposed to a centrally located server, IPFS is built around a decentralized system of user-operators who hold a portion of the overall data, creating a resilient system of file storage and sharing. Any user in the network can serve a file by its content address, and other peers in the network can find and request that content from any node who has it using a distributed hash table (DHT).
In contrast to BitTorrent, IPFS aims to create a single global network. This means that if Alice and Bob publish a block of data with the same hash, the peers downloading the content from Alice will exchange data with the ones downloading it from Bob. IPFS aims to replace protocols used for static webpage delivery by using gateways which are accessible with HTTP. Users may choose not to install an IPFS client on their device and instead use a public gateway. A list of these gateways is maintained on the IPFS GitHub page.
IPFS was launched in an alpha version in February 2015, and by October of the same year was described by TechCrunch as "quickly spreading by word of mouth."
The Catalan independence referendum, taking place in September–October 2017, was deemed illegal by the Constitutional Court of Spain and many related websites were blocked. Subsequently, the Catalan Pirate Party mirrored the website on IPFS to bypass the High Court of Justice of Catalonia order of blocking.