It isn't enough just to make what data comes your way pretty and easy to read, although that has a useful function too, undoubtedly.

These people need to be thrown out of work because they are performing no useful economic function.

Conflict also has the useful function of driving traffic to his sites.

But once it also served another useful function, marking the beginning of election campaign season.

However, he suggests that fear does have a useful function.

Oil prices in the current range serve other useful functions, some analysts said.

They are simply not capable of adding any useful function to the process.

Parties obviously serve a useful function for many voters - and they still can.

Some of the more commonly useful functions are detailed below.

"We have these emotions because they serve useful functions for us."