ERC20 token standard suffers critical problems, that caused loss of approximately $3,000,000 at the moment (31 Dec, 2017). The main and the most important is lack of event handling mechanism of ERC20 standard. ERC223 is a superset of the ERC20 token standard. It is a step forward towards economic abstraction at the application/contract level allowing the use of tokens as first class value transfer assets in smart contract development. It is also a more safe standard as it doesn't allow token transfers to contracts that don't support token receiving and handling.