To build an XBlock, you must have the following tools on your computer.
To run the a virtual environment and the XBlock SDK, and to build an XBlock, you must have Python 2.7 installed on your computer.
Download Python for your operating system and follow the installation instructions.
EdX repositories, including XBlock and the XBlock SDK, are stored on GitHub.
To build your own XBlock, and to deploy it later, you must use Git for source control.
If you do not have Git installed, or you are are unfamiliar with the tool, see the GitHub Help.
It is recommended that you develop your XBlock using a Python virtual environment. A virtual environment is a tool to keep the dependencies required by different projects in separate places.
With a virtual environment you can manage the requirements of your XBlock in a separate location so they do not conflict with requirements of other Python applications you might need.
After you have installed Python 2.7, follow the VirtualEnv Installation instructions.
For information on creating the virtual environment for your XBlock, see Create and Activate the Virtual Environment.