Arweave is a protocol for decentralised, sustainable and permanent storage of data with a one-off payment. The network is decentralised, like Bitcoin, and miners on the network provide hard drive space to those individuals and organisations looking to store data.
The storage is backed by a sustainable endowment, ensuring it is available in perpetuity.
On top of this core storage layer lives the 'permaweb' – an unalterable, censorship resistant web where applications and web pages exist indefinitely.
The Arweave network is powered by the $AR token, which is used to pay for storage. You can find details of the fees at arweavefees.com