This chapter started with an introduction to Bitcoin installation, followed by some discussion on source code setup and how to set up Bitcoin clients for various networks. After this, we examined various command-line options available in Bitcoin clients. Lastly, we saw which APIs are available for Bitcoin programming and the main points to keep in mind while evaluating APIs for usage. In the next chapter, we will introduce alternative electronic cash blockchain projects, that is, the digital currency projects other than Bitcoin, such as Litecoin and Namecoin. We will also discuss various ideas that led to the development of alternative coin projects.