This is the core of the millroadwinterfair.org website, all the pages we add to the site are of one of the types defined in the Core folder and the live site also has a lot of plug-ins.
The themes folder contains the themes we want to use based on whether the user is using a mobile device or not.
The modules folder contains the bespoke modules which have been written for the site over the years.
Currently the repo mrwf-environment doesn't work but the intent is that this repo is used in concert with that to make a test environment you can use to try out any changes you make. If you're happy setting up silverstripe locally and testing that way, by all means do that!