The Arweave network itself is a global, permanent hard drive, while the permaweb is a decentralised, immutable web built on top of the Arweave.
Permaweb apps are built using normal web technologies — HTML, CSS, and Javascript — but are deployed to Arweave’s on-chain storage system, making them permanent and available in a fast, decentralised manner. You can deploy a permaweb app in 2 minutes or less with Arweave Deploy!