Let say, in our website we define a city, say Paris. When a visitor surf this web page, we would like to show him a tours and hotels about this city. Currently, we can have it by adding module, however consider you need to add 100 city, it is become time-consuming and boring which may leads to insert information by high level of errors. In this context, it maybe useful to have a city category which is unified in Solidres, in each part of extension when we want to specify new tours or hotel we will refer to that city.
I think in this way both sides customers and web-admins will be receive benefit.