Chia is a cryptocurrency designed to embody the principles of decentralised consensus. It is an open source community-based system which runs without a central authority, currency, or stake. Instead, chia uses a Proof of Space and Time (PoST) model. PoST ensures the project can grow indefinitely without any resource constraints as each new block added to the blockchain account represents an additional piece of real estate, or time.
The unique property of Chia is that it has traditionally operated through Proof of Space and Time rather than Proof of Work. This is because PoW is a limiting and costly property while PoST allows nodes to download and store a space–time RBF history and records, without requiring them to actively validate transactions. Publicly verifying the existence of a particular piece of information is cheap.
The PoST, or Proof of Space, rewards users for extending their computer’s limited resources. This occurs through creating spaces for other Chia nodes to read and write data without exhausting the owner’s available system memory. The more work that other Chia nodes can be encouraged to do, and the longer they keep the space available, the more reward they receive.