Planning permission is required for the “material change of use” of a property. This is a change of the main use of a property, not ancillary uses, e.g. if a shop choses to change part of its customer area to an area where goods to be sold will be stored that is a change of ancillary uses. The Use Classes Order (see the entry below for this) specifies various categories of use and planning permission is not required to change the use of a property from one use to another in the same use class. 

A term often relating to Conservation Areas or Listed Buildings, but also to the appearance of any place in terms of its landscape or the layout of streets and open spaces, giving it a distinct identity.