Zittrain argues that today’s technological market is dominated by two contrasting business models: the generative and the non-generative. The generative models – the PCs, Windows and Macs of this world – allow third parties to build upon and share through them. The non-generative model is more restricted; appliances such as the xbox, iPod and tomtom might work well, but the only entity that can change the way they operate is the vendor.