Theme Cabins are this year's name for the Theme Camps last year. It is a nod to our heritage from Nest's site up until 2015. "Camp" and "Cabin" is interchangeable; it's okay if you use one, both, or either in your application. For the grammatically pedantic, emotionally prepare yourself for a range of capitalisations (Theme Cabin, Theme cabin, theme cabin -- it's a jungle out there).
There are six sections to fill out with approximately five questions per section. Some are long form (you'll need describe your answers) and some are numerical or one-word answers.