This document discusses blockchain technology and its potential uses. It provides an overview of blockchain as a shared, peer-to-peer ledger that establishes trust without intermediaries. It describes Hyperledger as an open source blockchain project with over 30 members like IBM and JP Morgan. The document also briefly discusses communities around Bitcoin and Ethereum, as well as potential applications of blockchain in government, finance, transport, art, and more. Finally, it suggests some possible uses of blockchain on the IBM Bluemix platform.