The development of the Cardano blockchain is guided by a methodical, research-based, and deliberate approach to innovation. Since Cardano’s first iteration as a federated network of just seven nodes, Input Output Global Inc. (IOG) has added many new pieces to the blockchain design, one at a time. Over five development phases, IOG introduced innovations, new functionality, and novel features, with each phase building upon the previous phase's achievements.
See the 'What IOG has delivered for Cardano' paper for a complete overview.