Polkadot is a sharded multichain network, which means it can process many transactions on multiple chains at the same time ("parachains"). Scalability is improved by the parallel processing power.
The Substrate framework makes it quick and easy to create custom blockchains, and Substrate blockchains are designed to be easily connected to Polkadot's network. The network is also highly adaptable and flexible, allowing participants to share information and functionality. Polkadot can be automatically upgraded without the need for a fork to add new features or fix bugs.
The network has a sophisticated user-driven governance system in place, with all token holders having a say in how the network is run. Polkadot allows teams to customize their own blockchain governance based on their needs and changing conditions. Nominators, validators, and collators all have different responsibilities in order to help secure and maintain the network and eliminate bad behavior.
Polkadot successfully completed its first parachain auctions at the end of 2021. The Parachain auctions used an unlicensed candle auction system. The winning bid is the highest bid at the time the auction ends at random.
Polkadot gave the first five slots to auction winners Acala, Moonbeam, Astar, Parallel, and Clover. These projects will have their parachain slots locked in for 96 weeks, as collateralized by the DOT bidders. All projects had previously been battle-tested on Polkadot's de facto testnet Kusama, as is customary.