Council Tax
Definition of Dwelling
In general terms any kind of house or flat will count as a dwelling, including second homes which are not let out commercially.
Caravans count as dwellings if they are someone's main home. Certain properties in multiple occupation where facilities are shared may count as dwellings as might parts, such as staff accommodation, of hotels etc.
Domestic lock-ups are also defined as "dwellings" but these are exempt from Council Tax charges.