Arweave (AR) is a decentralized storage network that provides a platform for the indefinite storage of data. It describes itself as "a collectively owned hard drive that never forgets," and primarily hosts "the permaweb" — a permanent, decentralized web with a number of community-driven applications and platforms. The Arweave network uses a native cryptocurrency, AR, to compensate "miners" for indefinitely storing the network's information. The project was initially announced as Archain and later rebranded to Arweave before its official launch.

Arweave operates on a modified version of blockchain technology it calls "blockweave," which uses a "proof-of-access" consensus algorithm — a modified version of proof-of-work. With proof-of-access, each new block is not only linked to the one immediately prior to it but to a random previous block as well, and both blocks are hashed to generate the new one. Miners are not required to store an entire blockchain, but they are incentivized to store more information to prove they can access the old blocks that are required to mine a new one. This system ensures the "collective ability to store and share information between individuals and across time to new generations."

Arweave's primary use case is to provide a platform for the indefinite storage of data. Its flagship permaweb is built on top of Arweave's "blockweave," a variation of blockchain technology in which each block is linked to both the one immediately prior and also a random earlier one. This structure incentivizes miners to store more data because they need to be able to access random previous blocks to add new ones and receive rewards. Arweave also unveiled "profit sharing tokens," which allow developers to receive dividends when network transaction fees are generated from their application, and it hosts incubators to support the building of permaweb-based apps.

Arweave was founded by Sam Williams and William Jones, two Ph.D. candidates at the University of Kent. Williams brought experience in decentralized and distributed systems to the project, while Jones' focus was on graph theory and neural networking. The idea for Arweave came to Williams while walking up a mountain in Scotland, and he later developed the technical details with Jones. After launching Arweave, Williams was later named an advisor to Minespider, a company providing blockchain-based supply chain tracking for the raw materials industry, and he has served as a mentor for the Techstars accelerator program. Arweave has launched a decentralized autonomous organization comprised of core community members to further the development and expansion of the network and its ecosystem.