Definitions

A Single bed is a standard sized Single bed.
A King sized single bed is the largest Single bed available.
A Double bed is a standard sized Double bed.
A Queen sized double is larger than a standard Double bed.
A King sized double bed is the largest Double bed available.
A King sized twin is two King size singles which are able to be used as singles or a King sized double.

En Suite means a toilet and shower for your own exclusive use, usually off the bed room.
Shared Facilities means toilet and shower shared either with other guests or family.