This paper presents a blockchain definition independent of any digital currency, and describes its characteristics including consensus protocols, design patterns, scalability, databases, and chaincode. The paper then presents a permissioned blockchain, called Beihangchain, with its unique consensus algorithms, interfaces, and design. It also proposes ABC (account blockchain) and TBC (trading blockchain), to be used for a variety of applications including copyright protection and digital payment. Finally, this paper analyzes chaincode requirements and provides guidelines for effective chaincode.