Understanding Poky
Poky is the default Yocto Project reference distribution, which uses OpenEmbedded build system technology. It is composed of a collection of tools, configuration files, and recipe data (known as metadata). It is platform-independent and performs cross-compiling using the BitBake tool, OpenEmbedded Core, and a default set of metadata, as shown in the following figure. In addition, it provides the mechanism to build and combine thousands of distributed open source projects to form a fully customizable, complete, and coherent Linux software stack.
Poky’s main objective is to provide all the features an embedded developer needs.

Figure 1.1 – Poky main components
BitBake
BitBake is a task scheduler and execution system that parses Python and Shell Script code. The code that is parsed generates and runs tasks, which are a set of steps ordered per the code’s dependencies.
BitBake evaluates all available metadata...