As professionals we use various technical terms to describe different balloon bouquets, sculptures and centre pieces.
Some examples:

String of pearl arch
A series of balloon attached to line which form an arch over a top table, cake table, and present table or even up a stair case.
String of pearl arches adds a soft and romantic feel to your reception area. These are normally made using latex balloon to match your colour scheme. However you can use the foil balloons or have a double bubble to crown the arch.

Bouquet of latex balloons
This can be made up of 3, 5 or 7 balloons to match your theme for the day. The balloons are normally blown to 11” and attached to a weight using ribbon. They can be placed on the table as centre pieces or tied long to stand on the floor to form a frame for your band or add the wow factor for your entrance.

Bouquet of latex and foil balloons
Are bouquet of latex balloons as above, but they are topped with a foil balloon – which can be a heart, circle or star. This just adds a bit of sparkle to the bouquet. Again they can be used as centre pieces or freestanding to use anywhere in the reception area.

Bouquet of foil balloons 
These will comprise of 3, 5 or 7 foil balloons in the colours of the day. They are also attached to a balloon weight and can be placed on the tables as table centres or placed by an entrance to add colour and create excitement about the reception area. These are a more expensive option, but will last for days – Particularly useful for weekend events!