Detailed coverage of configuration management is beyond the scope of this beginners' book but in short, this section empowers you to export either the entire configuration of your site; content types, taxonomies, views and so on as a single (zipped) archive or to choose to target one particular item such as a view to be exported as pure code.
It also enables you re-import and even provides a neat comparison view of what's changed in your configuration since you last exported it.
This section is enormously useful when it comes to deploying new or updated configuration from a development site to live.