Polkadot is an open-source sharded multichain protocol that connects and secures a network of specialized blockchains, facilitating cross-chain transfer of any data or asset types, not just tokens, thereby allowing blockchains to be interoperable with each other. Polkadot was designed to provide a foundation for a decentralized internet of blockchains, also known as Web3.
I think a great buy would be below the $10 dollar price - preferably around $7 dollars.