The technology behind blockchain has attracted a lot of attention. However, this technology is for the most part not well understood. There is no consensus on what benefits it may bring or on how it may fail. A careful look into the technology finds that most of the proposed benefits of so-called blockchain technologies do not really come from elements unique to blockchain. Instead, they come from more conventional elements such as encryption and smart contracts. Moreover, even those applications that would benefit from a distributed system may benefit more from a distributed database designed differently than blockchain.